40+ Mpg

[mechtech]

I am a fan of using a little oil in the gas to lube the FP and top end. Alcohol in modern fuels is not a good lubricant.
Lucas UCL is good, but expensive. I use 2 stroke oil at 2-4 ounces/10 gal gas.
But i just tried OUTBOARD 2 stroke oil. It's better for water cooled engines, leaves even less deposits, and does not affect octane as much.
One gallon is $9.00 at Walmart, so it's very cheap.

At the same time, I tried soldering in a 5.6k ohm resistor in series with my inlet air temp sensor. Yes, I know that this is similar to the EBay rip off thing. I tried this before at 2.4k ohms, with indifferent results, but this time I got immediate results.
My gas gauge would not move, I thought it was broken. When I got 200 miles and it was well above 1/2 a tank, I really started to take notice.
I drive easy, but wring her out every day, too. This is suburban driving, not really all city.
I don't think the computer will override this, because the air temps are within normal temps. 5.6 k ohm lies to the computer that it is 10-20 deg F colder than it really is [10 cold and 20 at hot air temps].
The extra cruising ignition advance must be the reason.
This is a big jump - like 5-8 MPG more than normal in these circumstances.
[It is not because of how I filled the tank,BTW.]
Power remains great, still gets 7-7.2 seconds 0-60 and granny shifting.

So give it a try in these overpriced fuel days.

[zxtuner98]

Isnt there any other productn thats not "oil" that we can use. Do you put it in right before you fill the tank?

[2TonCat]

Eww Eww Eww Eww!!!

Do not put that shit in your car!! I've used that in two 2-stroke dirtbikes, and one boat. Mind you these are vehicles this oil was designed for... All three vehicles would load up and foul spark plugs until the tanks were drained and refilled with Honda 100% synthetic 2-stroke racing oil.

Why are you putting oil in your fuel anyway?

[Twiggy2cents]

theres a diff..hes not putting much in it...just enough to add some lubricity to the gas

[Zx2 Frost]

so wait inlet air temp sensor, maf right?

If so which wires?

[zxtuner98]

My inlet air temp sensor[IAT} is in the side of my intake. I have a 98' tho.

[Zx2 Frost]

i have a 02

[Tygen1]

Mech, could the computer thinking the motor is running cooler, maybe cause it to add more fuel? Are you sure it's adding ignition timing and not retarding it?
Interestingly, I have recently, since the outside temps have risen, started to get a little pinging under cruising. However, all winter it did not. It's a stock '98 atx with the knock sensor pulled. It seems like the higher temps don't like the timing advance at cruise.
I might be visting radio shack tommarow cause 8mpg woud be a huge difference on my 80 mile per day commute.

[zxtuner98]

i really dont know what happened to the IAT's in 99 +'s. Were they integrated into the MAF? or just non-existant.

[david gettle]

In the 99+'s the IAt is part of the MAF.

[krux]

Aren't you getting any side effects though when at light partial throttle based on you will get your most advanced timing then. Any knock or ping? Just sounds kind of weird that its working. Since i would think you want to trick the computer saying its warm outside so that it goes to closed loop and thus making short trim and long trim close to each other. I would beleive you would get better gas mileage that way.

[Jrock909]

Where do you get those 5.6ohm resistors at? Please tell me Radio Shack ;-) How many wires are going to the IAT on a 98-99 ZX2?

[Jrock909]

Another thing mechtech how many watts is that 5.6ohm resistor>>>>?

[david gettle]

Isn't this kind of doing the IAT 1/2 of the POTS mod, but with a fixed resistor?

Also on a 6 wire MAF, what color wire does this get put into? (I'm assuming you put this at the IAT inside the intake housing).

[J_Mob]

Do you solder it in place of the actual sensor (wire) inside the maf or just inline of one of the wires, and which one?

Oil in the gas won't hurt.....it will burn slower. In deisel engines people used to pour their old engine and hyd oil in the fuel tank, or so I've been told. Don't know that I would try something that heavy in a gasoline, though I am sure it would burn. Alcohol/ethanol burns up quicker....and I haven't noticed any more power from it burning up faster in my experience (though I haven't tried any 150 octane or whatever it is - the race fuel you can get)

[mechtech]

1/2 watt and 5.6 k ohm was the rating, a pack of 6 at Radio Shack was a few dollars.

Top end lubes are very safe. Marvel Mystery Oil had been used for decades. At light doses ashless [and as I found, especially outboard 2 stroke oil] 2 stroke oil is great. Lubes the pump, injectors, valve guides and rings a bit. Also helps seal the valves a and rings somewhat.
I put my dose of oil in the tank, then fill it. like I said , 2-4 oz/10 gal gas, and more is NOT better.
Cat converter? This 2 stroke oil burns pretty clean. I am not worried at all.

This is kinda like a 1/2 POTs mod, but with much less resistance used [and no switch]. I considered the temperature/resistance chart of the IAT sensor, and decided on the 10-20 deg F change.
I used the white/green tracer wire for the IAT near the MAF. Easy to do, and reversible.

I did not say it lied that it was WARMER, but that is lied to be COLDER - thereby gleaning a few more degrees ignition advance - obviously at part throttle as well.

If anything, the computer should add a bit of richness, but the O2 will take care of any minor amount. I seems the coolant sensor has the big effect on richness.

I'm on my second tank, and so far so good.

[david gettle]

Thanks for the clarification, looks like My MAF is getting taken apart, and modded some more ...

I've used Mystery oil in the past in other cars, just not this one.

[Thnikkaman]

Does the oil in the fuel contribute to the increased economy or is it just the resistor?

can oil in the fuel alter the octane number?

[AZN_ZX2]

hm a how to would be cool. good job though man

[00EscortZx2]

Mech knows more about Zx2's than Ford does. I'd take his word for it.

[david gettle]

The RadioShack part# for the resistors is 271-1125. They are normally located in the parts drawers.

[scort2498]

maybe some pics on how you did it for us that know jack crap about wires.

[xtremecaraudio]

sounds interesting, I never really thought about running 2 stroke oil in this car. With my mileage where it's at it might prolong life a bit.

I remember in my 88 rx7 when I had it I ran premix after my omp went out to keep the rotors lubed which I plan on doing my new one as well since the 2 stroke oil lubes better than the 4 stroke. I'll have some around anyway I give it a try in the zx2 I suppose.

[Buster]

Great job, Mech.

Keep us updated with the results and if there are any negative effects.

I may try this but I don't want to do anything to decrease the car's lifespan. :)

[TTFOWIA]

interesting.

[PHeller]

Yes, will need a how too. I don't know anything about wiring except basic stuff, but i'll learn for a 5-6mpg jump.

[FatTonyZx2ner]

Step 1, cut wire.
Step 2, solder resistor to 1 end.
Step 3, solder resister to other end.

lol.


kindding. not sure on wires. There would need to be info for those that have both the 4 wire maf with seperate IAT and those that have the 6 wire with integrated IAT

[J_Mob]

I'm gonna try it when I get my ZX2 back in working order. Cut/solder/tape @ white w/green stripe wire correct?

[mechtech]

Yeah - it's that simple. Make a good connection[s] mechanically, then solder it.
I used the wire near the MAF - it was easiest. You can use either IAT wire - it is in series.

I'm sure the resistor gave me the big jump, I used 2 stroke oil before. The outboard type is much better for cars - just don't go heavy on the dose.

I'll keep you posted as time unfolds, and hope you'll do the same.

[gunman_sr5]

I am trying the 2 stroke oil now. I will probably get the resistor this weekend. Anything helps driving 600 miles a week.

[mechtech]

600 miles a week?!
Get adopted by an Arab Sheik!

[gunman_sr5]

lol tell me about it. If I get my new house I go to 500 a week, but still.... Anything helps.

[david gettle]

500 a week

Been there, done that.... Not fun!!!

[gunman_sr5]

No it isn't but considering its 100 miles less a week then what I drive back and forth to work now. Add to the fact I have no cruse in my car. I hope to be adding it soon. No big deal though I have been doing this for 2 years already.

[PHeller]

Mechtech, could the Resistor Trick work without using the oil?

Aren't you worried about burning valves by running too lean?

[iceracer]

It is called Top Cylinder Lube. I use Mystery Oil. There are many others. I see no reason a 2cycle oil wouldn't work.
TCL lubricates parts that don't see oil normaly. Valve stems for one.
You add only 4-8oz. to a full tank.

[gunman_sr5]

The resistor works without the oil to. Like iceracer said. Its just for lubricating the top end components.

[zxtuner98]

im gonna pick some up, not like the more and more alcohol they're putting in gas is lubing anything

[mechtech]

PHeller - The resistor and lube are really separate. It just happened that I changed them at the same time.
The lube is a good idea, but remember LIGHT doses.

As to being lean, I don't know why you state this. The car won't run lean with an O2 sensor, and if anything, this should richen it up. A lot of heat can burn a valve, but it is very rare to see it unless you are racing. A lean mixture won't burn a valve by itself, anyway.

[PHeller]

so which wire are we adding this resistor to again?

[david gettle]

White(gray) wire w/green stripe at MAF.

[PHeller]

I'd like to see where people are splicing it. Some people said they were going to take apart the MAF, but I'm not so sure you need to do that in order to find that wire. Right?

[david gettle]

I installed it in the white wire with the red stripe in the short wiring harness that is partialy inside the MAF housing (the one with the rubber peice around it). so the resistor is hidden inside the MAF housing. I'll post a picture later.

[PHeller]

White(gray) wire w/green stripe at MAF.

I installed it in the white wire with the red stripe in the short wiring harness that is partialy inside the MAF housing


Ummm...yes...a picture will be needed.

[mechtech]

It seems that Mr. Gettle placed/hid his resistor more discreetly than me. Therefore he used a different wire [inside the MAF housing].
But it is easy from the outside where the wires go to the MAF. Anywhere along the length is OK. Outside, you use the White/grn tracer.

I think this mod may give 1-3 degrees more advance, allowing more cruising efficiency . It might give a bit more power - tough to measure that. I might play with resistors and a timing light if I am in the mood some day.

[DOUGIESTYL]

I've been using a 1/2 bottle of Stihl full synthetic 2-cycle oil in my tank at fill-up for years, now. I notice an increase in oompf after putting it in after a tank without it! I go abck and forth between that and CD-2 lead substitute. If you have a slight bit of lube in the upper cyl. you essentially have less friction, which is the destroyer of engines (friction,that is)

[TSmiley98]

this is from ford tech service, the temp values related to the voltage readings and the resistance the sensor puts out at given temps..

http://i113.photobucket.com/albums/n227/tsmiley98/cars/car%20stuff/temps.jpg

[mechtech]

That chart got cut off. The IAT sensor sees -20 deg F to 140 deg F in normal life.

[david gettle]

Here's that photo I promised...
http://inlinethumb01.webshots.com/41856/2685962900057438685S600x600Q85.jpg

[Twiggy2cents]

this is from ford tech service, the temp values related to the voltage readings and the resistance the sensor puts out at given temps..

http://i113.photobucket.com/albums/n227/tsmiley98/cars/car%20stuff/temps.jpg

shhhh! how do you know the uber top secret website? lol

[Jrock909]

Anybody else seeing any gas mileage improvements with the resistor yet... I am trying out mine now with a full tank of gas, down to half a tank and seems to be working ;-)

[david gettle]

Yes, I'm at 1/2 tank of gas and have driven 250 miles since installing this (I filled up the day after I installed this).

[gunman_sr5]

nothing noticeable yet, besides an 1/8 of a tank that mysteriously disappeared overnight. So I am 50 miles short on my tank right now....

[PHeller]

So you guys are getting MPG and Power gains in everyday driving?

As in, you aren't actively changing your driving style from before you installed the resistor?

It just seems to good to be true, and I'm mad excited to try it out.

[gunman_sr5]

I have been milking everything I can from the Z for the past couple months. So no changes in my driving.

[TSmiley98]

i am thinking of trying this on my mazda B2500, , i have already taken off the fan and clutch, repalced with an electric fan that has gained, about 2 mpg, in town..

[Jrock909]

1/2 tank and you are at 250 miles??? No way I am at 195,000 and almost at a 1/4 of a tank.. I normally come up with around 250-270 miles give or take. I drive spirited most of the time though ;-)

[ZX2 Sleeper]

This seems to work... Im going try this soon! Thanks Mech! Average cost of resistor? Maybe i can squeeze some change outta my piggy bank!

[mechtech]

On any other car, the resistance values will be different, and due to programming or other factors, it may not work.
My second tank is not as good, but still above normal. Different crappy conditions, though.

I am not selling anything, but I sure hope it helps for you guys. [Or, You All!]

[ZX2 Sleeper]

As far as the oil additive. I hope you mixing it with some gasoline before you introduce it to the gas tank. People who have 2 stroke engine dirt bikes like mixing with gasoline to get all the oil and also have a nice mix.

[david gettle]

I just filled up, and the difference was about +3% but I did run the defroster quite a bit this tank (cold rain making the windshield fog up) witch I have not had to do in a while in a while.

[1981gMachine]

if all the 2cycle stuff is for lube then try Brad Penn oil. It's the best out there and it's formulated to stay on the metal parts, soaks into them. I run their race oil in the camaro and buddy uses their synthetic in his Audi and Mazdaspeed3.

[2KZX2]

Does anyone have this setup paired with an UDP, or upgraded exhaust and intake? Sounds like this might be worth trying, especially since I can already get up to 35-38 mpg, if I drive nicely.

[gunman_sr5]

My mods list is in my sig. I pulled 35.567 with some mixed rural/city driving. I think I may have had some fuel siphoned out of my tank though. I will have more solid numbers in about 3 days.

[5spd07gt]

my 98 is completey stock with only a k&n replacement filter and i just checked my mileage today, 41.4 mpg, no joke, i double checked it. Its a 5spd

[david gettle]

My mods are...
Kemen air box mod, Crazyguy MAf mod, Powder's UDP, ZXTuner "Roush" style intake, ATX shift Kit, Trubendz 2.25" cat back (Magnaflow resonator, Aero-Turbine Muffler), JBA short Header, 19mm RSB, Heavy duty sway bar end links (all four), Wings West kit, JSP apachee spoiler, grill mesh in front bumper. the car was driven stock for 1 year after purchase, average MPG from date of purchase (03/07/2002) to 5/12/08 was 29.878 MPG

[ZX2 S/R Black]

my 98 is completey stock with only a k&n replacement filter and i just checked my mileage today, 41.4 mpg, no joke, i double checked it. Its a 5spd

wtf...lol u must do only highway... I get 20mpg :(

[5spd07gt]

it was mainly highway but some city driving. my neighbor said he gets 40mpg and my brother has a 99, he got 37mpg his last tank

[2000zx2chik]

wtf...lol u must do only highway... I get 20mpg :(

thats about what i get and i got an automatic :/

[Jrock909]

what does it do when you run the defroster, does that drag on the engine David..?

[mechtech]

2 stroke bikes need the oil for lube. It HAS to be mixed right at the beginning.
There is no harm in premixing, but no one is going to carry around a can of premix. A squirt container of 2 stroke oil is handy and inoffensive, though.
But for a car, putting your lube in, then filling it seems to work perfectly. It mixes then, then more as you drive.

[david gettle]

what does it do when you run the defroster, does that drag on the engine David..?
Short answer, yes.

Long answer; In the ZX2 (and all other ford Escorts since 1989) when the defroster is on the car runs the A/C compressor to dry the air inside the passenger compartment, causing the engine to work harder to make the car travel at the same speed.

[j0hnZ]

I get really good gas mileage in my new/older zx2. I got around 30mpg which rocks for me. I shall try this soon maybe this weekend.

[mechtech]

That's because the 2 stroke engine HAS to have the oil there for lubrication.
We don't.
Add to your tank, and fill with fuel. It will mix then, and as you drive.

[gunman_sr5]

I inadvertently dumped 8oz in this last tank. It hurt my mileage. 4oz is definitely the limit.

[ZX2 Sleeper]

What is the exact resistor i need? I think i got a 5.6k ohm one, but i wanna make sure all the other specs are correct before I attempt this.

[david gettle]

To answer your question^^^, 5.6k-Ohm 1/2 watt 5% tolerance RadioShack part #271-1125.

[gunman_sr5]

$.99 for a 5 or 6 pack Can't remember. You may have to ask for then. They where not in the resistor bin where I got them.

[ZX2 Sleeper]

Thank you gunman!

[Jrock909]

Okay David thanks for clarifying that bro.... Now if I run the heater on the vent or vent/floor will that also run the a/c compressor...?

[gunman_sr5]

I think vent is the only thing that doesn't run the A/C. Anything else caused my compressor to run. I just disconnected it, but it still caused my idle to go up in anything other then vent or off.

[J_Mob]

I think vent is the only thing that doesn't run the A/C. Anything else caused my compressor to run. I just disconnected it, but it still caused my idle to go up in anything other then vent or off.

Yeah I noticed that too. I disconnected the compressor and the sensor and it still seems to make her idle wierd when the heat/def is on. I think i need to remove the whole ac setup. Hell, I can always roll the windows down right.....:biggrin:

Gonna try this mod as soon as I can get to ratshack........

[Technik]

i usually get about 25 to 29 city and i got about 36 when i drove mostly highway. i have a 2000 atx with Knocker mod and Rousch style intake and K&N drop in

[gunman_sr5]

Well my numbers are in for 50-60 degrees and rainy with my oops 8oz of 2 cycle oil and resistor mod. 35 MPG thats 2 MPG better then I would normally get in these conditions. Hopefully it warms up to 80 next week like its suppose to. I got 37 in those conditions before the oil and resistor.

[Buster]

I think vent is the only thing that doesn't run the A/C. Anything else caused my compressor to run. I just disconnected it, but it still caused my idle to go up in anything other then vent or off.

I believe it's "just vents" or "just feet" that won't kick the AC compressor on.

If you run both, it's on. Defrost is on. Of course, AC it's on.

[J_Mob]

Okay since getting my car running, I just filled up for the first time and checked the mileage.....est. it at about 26 MPG currently. (Now part of that was driving about 30 miles on the freeway in second gear the whole way so I expect it should be more around 28). I am wiring in the resistor tonight, and will let ya'll know next time I fill up if there is an improvement.

I am in a 2000 ZX2, ATX (out of a 4-door 99 Escort, SOHC I believe), and the only mod I have made so far is Kemanized the intake(cheaper then a CAI, though I may still get one later)...... I am thinking about putting together one of those shift kits in a little housing and try wiring it in maybe as well.

[david gettle]

The ATX kit will add to MPG also(though not as much as the MAF resistor), I would suggest an additional tranny cooler also, the one in my car is mounted between the radiator and the A/C condensor.

The A/C compressor should only run when the A/C is on, or when the defroster is on.

[J_Mob]

Yeah I am going to the scrapyard tomorrow to find a cooler or small radiator to rig in line with my stock cooler. I am thinking just cut the steel lines, use rubber lines to connect it to another cooler, and mount it in front of the radiator or on bottom of the car somehow.

I did the resistor and the shift kit (ghetto-tastic electrical tape wrapped black box mounted above my cupholders now) stage 1/2 switched via the diagram in D.I.Y. section. I filled the tank earlier, and drove it just now 23 miles, and the gas gauge has yet to move so I'm hoping for good things.................

Edit-On second thought.....if I was to take out the AC system, what opinions are had on using the ac condensor as a trans cooler? It may be too small of channels inside for oil, but it's already there.....................

[havocsmaster]

resistor is soldered in....will post my results when i check my mileage...hell even 2-3 MPG increase would be worth the effort of trying this out!!

[JonsZX2SR]

Premium or synthetic 2-stroke oil at 200:1 to 400:1 ratio in the gasoline will not foul the plugs, especially after the O2 sensor adjusts the A/F ratio. As mechtech says it does lubricate the top end of the engine and reduces wear.

[scort2498]

so if we had a pre 99.5 with the iat seperat would we wire it in the iat? and is so which wire would that be?

[DaviDawg]

this should help
http://i298.photobucket.com/albums/mm254/davidawg/DSC00671.jpg

[RedRacer99]

i'll have to try this in my saturn... hey question, can you do this without messing with wires? like, just pour some 2 stroke oil in at the tank before i fill up? the oil makes sense though...

oh, pardon my noobness, but two stroke oil is the same as 2 cyl oil like used in lawn mowers right?

[Boski]

what will this mod do in the winter. when the temp is well below 30 degrease F? i really want to do it tho maybe ill runto the junk yard and find another MAF wire harness and trade them out in the winter

[Twiggy2cents]

i'll have to try this in my saturn... hey question, can you do this without messing with wires? like, just pour some 2 stroke oil in at the tank before i fill up? the oil makes sense though...

oh, pardon my noobness, but two stroke oil is the same as 2 cyl oil like used in lawn mowers right?

yes that is the same oil and your gonna have to mess with wires for the iat part... the oil wont really increase your mileage it will just help prevent wear the real mod is the resistor for the iat

[Twiggy2cents]

what will this mod do in the winter. when the temp is well below 30 degrease F? i really want to do it tho maybe ill runto the junk yard and find another MAF wire harness and trade them out in the winter

prob nothing, its like pots but less aggresive... if for some reason it runs like crap take it out its not a big deal but i dont think it will

[mechtech]

Remember that I recommended the OUTBOARD 2 stroke oil - it is best for us. Super cheap at $9/gal at Walmart. It can help lube and seal, and there may be a slight performance benefit - a little MPG increase.
AT 30 deg F, the 5.6 K Ohm resistor lies to the computer that it is about 20.
There is variance in our 5V regulated voltage, and variance in IAT sensors, even brand new.
I picked the 5.6 k ohm because it is a mild shift. Maybe more is better in some conditions.
You don't need another MAF, just reconnect the wires, or bridge the resistor with a wire if you want to revert to stock.

BTW, this tankful went WAY down on my car, but It is entirely because of stop and go parking lot in rush on the highway driving all week. Just over 30 mpg, but remember we get 0 mpg when not moving.

AC is OFF in 'off', 'vent', and 'floor'. It is ON in all other positions.

[havocsmaster]

what kind of numbers could you expect with ambient temps running in the 80-100* range? just curious since thats what temps average from march till late september here. would a different resistor be more to my benefit? opinions welcome!

[2KZX2]

Since I have a 2000 zx2 would I use the red/white wire or the green/white wire, I know you said green/white, but I saw a picture of this done on the red/white, and according to the diagram above the red/white wire is the 02 sensor.

[J_Mob]

i'll have to try this in my saturn... hey question, can you do this without messing with wires? like, just pour some 2 stroke oil in at the tank before i fill up? the oil makes sense though...

oh, pardon my noobness, but two stroke oil is the same as 2 cyl oil like used in lawn mowers right?

What kind of saturn? I had a 95 SC1, and when I put the ebay CAI on, I couldn't figure out what to do with the temp sensor so I threaded it into the frame in front of the hood.....it was constantly exposed to fresh air while driving. I got close to 40mpg with that little bitch hehe.

[RedRacer99]

2006 ion 2 sedan auto.. i like it and it gets better gas mileage than the zx2 did

[mechtech]

havoc What kind of numbers???

[1999ZX2]

this should help
http://i298.photobucket.com/albums/mm254/davidawg/DSC00671.jpg



except for dummy's it does not show WHERE to put the 5.6K resisteeer :cyclops:

[havocsmaster]

havoc What kind of numbers???

i mean, would a different resistor work better in hotter climates, or should the one you installed be sufficient to see mileage increase, no matter what the temp?

[mechtech]

I picked 5.6 k ohms because it was not drastic, yet was sufficient to cause a significantly lower reading to the computer.
I did no testing with various impedences and a timing light.
Normal temps are -10 deg F to 125 [air inlet temp] . This resistor in our cars will show about a 20 deg lower change when very hot, to about 10 deg change at very cold.
Maybe a little more/less is better. I and others have had decent and immediate results with this, so I must have made a good guess.

[99fordzx2]

Does this work with ppl that have done the knocker mod?


-D

[gunman_sr5]

yes

[ZX2 S/R Black]

So yea I filled up earlier this week... 17mpg... I seriousley need to fix this issue

[AZN_ZX2]

So I bought the resistor. I'm worried about any long term affects this might have on the car since it needs to last me a while. Any risks?

[david gettle]

The only risk I know of is the risk of spending less on fuel.

There isn't a car that has had this done for a long period of time. But Mechtech is one of the more knowledgable people on the site about these cars, so for what that's worth I'm willing to try a mod that he comes up with, if for no other reason than the amount of time he has been on TeamZX2, and has not (to my knowledge) ever steared anyone in the wrong direction when it comes to mods for the ZX2.

If we find out there is a problem caused by this it is really easy to remove.

[ZX2 Sleeper]

Matt if there's issues.. i'll let you know. I have extra resistors so if you can solder good, you can have one! Im going to be doing mine saturday if i pass inspection tomorrow.

[AZN_ZX2]

Matt if there's issues.. i'll let you know. I have extra resistors so if you can solder good, you can have one! Im going to be doing mine saturday if i pass inspection tomorrow.

haha alright thanks man. i got 10 resistors already! we need to chill soon though

The only risk I know of is the risk of spending less on fuel.

There isn't a car that has had this done for a long period of time. But Mechtech is one of the more knowledgable people on the site about these cars, so for what that's worth I'm willing to try a mod that he comes up with, if for no other reason than the amount of time he has been on TeamZX2, and has not (to my knowledge) ever steared anyone in the wrong direction when it comes to mods for the ZX2.

If we find out there is a problem caused by this it is really easy to remove.

Alright cool thanks for the info man

[potatoman]

The only risk I know of is the risk of spending less on fuel.

There isn't a car that has had this done for a long period of time. But Mechtech is one of the more knowledgable people on the site about these cars, so for what that's worth I'm willing to try a mod that he comes up with, if for no other reason than the amount of time he has been on TeamZX2, and has not (to my knowledge) ever steared anyone in the wrong direction when it comes to mods for the ZX2.

If we find out there is a problem caused by this it is really easy to remove.

ive seen him steer people wrong before. lol. i believe it was a joke tho. and more than one person set the OP straight. i wouldnt worry about this tho. if u notice lower mileage then take it off. as long as ur car seems to run fine it shouldnt do any damage.

[1981gMachine]

Dumb question

Get these resistors at radioshack? What do they run price wise?

[pnutcar]

this should help
http://i298.photobucket.com/albums/mm254/davidawg/DSC00671.jpg

So these are the major changes for these cars? I have an 01 auto, so I'm guessing its the white/grn wire for me too then?

[AZN_ZX2]

Dumb question

Get these resistors at radioshack? What do they run price wise?

yup 0.99 for a 5 pack

[nate437]

Hey guys, I have a '99 with the separate IAT and MAF setup, where would I solder the resistor in at?

[gunman_sr5]

Either wire on the IAT.

[mechtech]

Because of horrid driving conditions [2 hours a day and never see 5th gear -slow and PITA driving] I got about the worst mileage I ever got this last tank. 28.4MPG.

But this tank is under normal driving conditions. Over 80 miles and still above the full mark. This tank will be a good one.

[2001zincsr]

make sure to reinforce your soldered resistors! Both mine and my buddy's broke within a week. Both were soldered well and electrical taped, but they broke off where the fine wire goes into the resistor. This time I put shrink tube over it and then covered that in a hard plastic sleeve I found laying around and then taped it. Hopefully it wont break again.

My gas mileage was looking good until it broke, then I only got a little over 100 miles to the second have of the tank. I couldnt figure out why I was loosing so much gas until my buddy said his broke.

So if you did this mod and all of a sudden started getting shitty gas mileage, check your resistor to see if it broke.

[J_Mob]

Allright-the results are in (on my ride anyways). 2000 ZX2, ATX, Kemanized the intake, and installed the resistor and the ATX shiftkit from the DIY section on the same day. I averaged around 28-29MPG in town (about 80% city driving, mixed with short spurts on the highway).

I had to run out to my cousins just now after filling the tank, which is 95% highway......filled it back up when I got home. Took about 2.25 gallons for 77 miles....roughly 36MPG hwy.

Not bad, considering the way I drive. I like to accelerate quickly.....lead foot or whatever you want to call it.

[LiveWire]

The same 2 stroke oil was discussed on a diesel forum and I was trying it in my Jetta when I read this thread. I have gotten 42 babying it, but can't handle that for more than a tank or two. I get 38-39 driving fast. Mileage was 38.1 on the previous tank and 40.4 on the tank with the oil. Those numbers are also getting my fuel at a station that sells 20% bio diesel which also gave me around a 2mpg increase which I attributed to more lubrication in bio diesel than regular diesel. So there is probably a limit to the total gain. I am up about 10% total which is what others say they are getting with the 2 stroke oil and regular diesel. Diesel already has more lubricating properties than gas so I could see it making a bigger percentage difference in a gas engine. I believe the oil also gave an improvement in performance because I have been inadvertently squealing the tires more lately. Adjusting my driving to that should net me a little more mileage. I'll run the oil in my ZX2 when I start driving it again, but not the resistor since I already have a chip in it and it most likely is already advancing my timing.

People question this being run for a long time. Since it is half the POTS mod, it has been.

For those who have not, I would also disconnect the knock sensor. On the ATF, I would do the resistor mod for firmer shifts. Slipping the clutches during the shifts is not helping your mileage any either.

[J_Mob]

I could see adding oil to diesel helping. People like using "red" fuel since it burns slower......with a slower burning fuel you should notice more low end power. (To an extent...I've heard of people using hyd and eng oil in the fuel tank and I know the army used multi-fuel engines back in the day, but I would think too much oil wouldn't burn easily enough to combust properly..)

I've heard good things about the TDI Jettas....guy at work drives one and says he regulary gets above 40, and says it is pretty fast. I've never driven one, so it's all secondhand.

[LiveWire]

A ZX2 will beat it. I did just beat a Civic with mine the other day :rocknana:

The chips are supposed to wake them up big time.

[tweakfreak]

If I can find my SCT X-2 I will do a case study on this. This in conjunction with other practical methods of fuel saving which include not only physical modifications but driving style(hypermiling). The ignition advance makes sense and like stated the o2 sensor will maintain stoichiometric AFR at part-throttle(closed loop). It would be interesting to find the point of diminishing returns with the resistance value.

Perhaps w/ a homemade MPG gauge I can have a more accurate and controlled measurements as opposed to using the old drive a bunch fill up at the pump and divide method. We shall see.

[J_Mob]

Don't most cars have a trip odometer? Thts what I've been using...I know it's just an average and all but hey.

[tweakfreak]

Doesn't seem too hard to do.

http://forum.ecomodder.com/showthread.php/mpguino-release-one-workspace-2115.html

[tweakfreak]

Come to think of that, this looks like a VERY solid product.

http://www.scangauge.com/features/

Apparently there is a USB interface that can be used for datalogging similar to that of an SCT device.

EDIT: This also looked good:

http://www.obdkey.com/index.asp I like the fact that this is open source.

[J_Mob]

Doesn't seem too hard to do.

http://forum.ecomodder.com/showthread.php/mpguino-release-one-workspace-2115.html

Crazy. I wonder how accurate it is.......

[mechtech]

Even if the exact accuracy is off, the relative accuracy for changes to the engine or management will be quite useful.
Scangauges are good, but expensive.

[J_Mob]

.
Scangauges are good, but expensive.

Yeah, a kid I work with bought a Mac scantool....paid like 700 bucks for it. (It's only been used the 2 times I borowed it to check this ZX2). I can't convince myself to spend that kind of money on one..........plus you have to buy updates every few years.

I just need to find software to put on my laptop. I know it's out there, but is probably just as expensive.

[00zx2s/r]

noob question- I was told that sr's need to run a higher octane gas. So I've been using mid-grade, because of cost. Since I'm running mid grade, should I still only use 4oz of oil or do I need more or less?

[tweakfreak]

I don't think it will affect the ratio enough to make an adjustment.

[mechtech]

2 stroke oil does lower octane a bit.
With our small amounts added, it should not be a problem.
Outboard 2 stroke oil is better than air cooled 2 stroke oil in this respect, anyway.
Play with it 2-4 ounces/10 gal gas and see if there is an amount your car likes.

[LiveWire]

I had tried some synthetic racing 2 stroke oil in my Excursion and it only made a slight improvement. The reduction in fuel usage was roughly that of the oil added. I got an improvement in the Jetta with the cheap crap and the Excursion has it in the current tank. The synthetic is made to handle higher temps so it probably does not burn as easily. At under 1/4 the price, the cheap Walmart/Meijer stuff is the way to go since this whole thing is about saving money.

[00zx2s/r]

If I read ur statement right, LiveWire, fyi- it's not the oil that gives the better gas mileage. It's the resistor that does. The oil is just for keeping the head lubed in areas that normally don't.

Hey mech- I hooked up the resistor and when driving around my CEL light came on... Code P0113- IAT circuit
Explanation: The Intake Air Temperature signal is used as an input for various systems in the vehicle.
Probable Cause: 1- Check connector and wiring
2- Sensor open or shorted-replace sensor
Is that normal or did I just not connect mine well enough? And w/ the 6 wire maf, you use the "gray" w/ red line right? Thanks!

[PHeller]

Do you guys buy the resistors in a pack or in singles? If someone bought a bunch, could they send me one? I'll give you points.

[00zx2s/r]

NVM about my earlier post, I got it fixed. Turns out it wasn't connected 100%...

And PHeller- you might as well go to radioshack and get them yourself. You can get a 5 pack for $0.99. lol I mean, somebody could ship them in stamped envelope, but it's easier to get em urself. But if there's not a radioshack around you, lemme know, I have 2 I can send u!

[tweakfreak]

Basically all the resistor mod does is bring the buffer between ignition and the threshold for pre-detonation a little bit closer together(hence improved fuel economy). Typically factory tunes are conservative so there is a potential for some gain I suppose. How much is there to be gained? Questionable, it will based on response from members and a little bit more of a controlled environment when I do testing this summer. I will be able to measure spark and fuel consumption rate... the two things we are modifying.

[iceracer]

Pre-destination= act of god. Hmmm.

[powder]

Subscribed.

[gunman_sr5]

I have gone w ith and without the oil now. I see better mileage without, but its also warmer out now. So I am going to have to try it again after the temp is steady.

[PHeller]

Pre-detonation= act of man. Hmmm.

Ah yes...

[PHeller]

Could we get a list of people who have done this and their noticable gains in the first post?

That would be great, something to this extent:

BlahBlahJoeZX2: +3mpg avg
JaneBahZX2: +5mpg avg

Something like that?

[LiveWire]

If I read ur statement right, LiveWire, fyi- it's not the oil that gives the better gas mileage. It's the resistor that does. The oil is just for keeping the head lubed in areas that normally don't.

Hey mech- I hooked up the resistor and when driving around my CEL light came on... Code P0113- IAT circuit
Explanation: The Intake Air Temperature signal is used as an input for various systems in the vehicle.
Probable Cause: 1- Check connector and wiring
2- Sensor open or shorted-replace sensor
Is that normal or did I just not connect mine well enough? And w/ the 6 wire maf, you use the "gray" w/ red line right? Thanks!

No, I believe both have the potential for an increase in mileage. Better lubrication means less drag so less power loss. My comments were that I did not see an improvement using expensive oil, but did with cheap oil. The next question for me is the exact amount that gets the most gain.

I may even try the acetone thing again. I did not get a gain from that when it was being hyped up. I actually lost mileage. Being a solvent, it would have a negative impact on the lubricity of the fuel. So after getting good numbers on the gain from the oil, I may try also adding the acetone again to see if the combination of the two gives a bigger gain than just the oil.

[Zx2 puller]

i'm gonna try this on my truck prob next week

[hollxiter16]

ok so i have a 98 exactly what wire do i cut and put the resistor in?

[tweakfreak]

Fixed the typo... it was a good one lol.

[gunman_sr5]

ok so i have a 98 exactly what wire do i cut and put the resistor in?

pick either wire going to the IAT and put it in there. Thats all I did.

[mechtech]

My mileage is up substantially.
'In horseshit driving conditions, I just got 34.5 MPG.

The outboard 2 stroke oil is mainly for lube.
It does help seal the valves and rings a bit, and lube the top end as well as the fuel pump,so there may be better performance and gas mileage from using it. But only a little.
My main MPG gain came from the resistor and warmer weather. But it was never this good in warm weather without the resistor.

[00zx2s/r]

pick either wire going to the IAT and put it in there. Thats all I did.

hey mech! is that ^ right? I thought it had to go on a specific wire??? The temperature one. Because the other ones measure air flow and all that...

[gunman_sr5]

Not on the 98 4 wire MAF separate IAT setup. I am prety sure either will work, or I just got lucky.

[2TonCat]

hey mech! is that ^ right? I thought it had to go on a specific wire??? The temperature one. Because the other ones measure air flow and all that...

These cars (and most 2000+ fords) have the Intake Air Temp sensor integrated into the MAF. Some of the wires there are for the MAF, and 2 are for the IAT. I saw a diagram of the wiring a couple pages back I think.

[mechtech]

00 - The IAT has two wires, whether separate or integrated into the MAF.
Use either one. It is a series circuit - it won't matter before or after.

[hollxiter16]

ok so solder it in 1 of the 2 IAT wires. thanks.

[J_Mob]

28mpg avg again this tank.....looks like that's gonna be about it for me. Stupid ATX. Stupid lead foot.

I guess I could change both of them if I really felt like putting forth the effort....nah.

[Technik]

i still havent put my resistor in yet and i got about 29 mpg city on my last tank with an atx but with gas at 410 or 420 a gallon i would love to see an increase. will it have a smaller effect on my car because i have an atx?

[DaviDawg]

i got 28 mpg my last tank with the resistor in but i went through half a tank smashing through the mountains with a group of friends. when i say smashing, i mean blasting!

[J_Mob]

i got 28 mpg my last tank with the resistor in but i went through half a tank smashing through the mountains with a group of friends. when i say smashing, i mean blasting!

hehe....:beer:

[phordzx2]

I just came back from a 1600 mile trip in my 98 zx2 5 speed last week. With the cruise set on 65 most of the way (speed limit through the mountains of Virginia and Tennesee) and fuel power and lube control, 45 psi in front tires 185/60 tires and aluminum swirles, stock intake, paper fram filter, I managed 40.4 and 39.5 on two 300 mile runs using cruise and downhill coasting as much as I could without getting ran over. This is the website of the stuff I've used and had crazy good luck with on most of my cars. http://www.lcdinc.com/ I'm not pushing it, just am a satisfied customer. There was a lot of hill climbing and I had the a/c on as well. HWY mileage and cruise is where its at for high MPG.

[LiveWire]

I'd rather pay $9 a gallon than $50 a gallon.

[phordzx2]

I'd rather pay 3.80 for shell 87.

[LiveWire]

I'd rather pay 3.80 for shell 87.

The additive you linked to sells for $50 a gallon vs. $9 a gallon for the 2 stroke oil.

[iceracer]

I read some interesting stuff about low rolling resistance tires. They are used on the Prius and the Insight. Suposed to increase your gas mileage. How much was argueable.

[AZN_ZX2]

I read some interesting stuff about low rolling resistance tires. They are used on the Prius and the Insight. Suposed to increase your gas mileage. How much was argueable.

They also provide almost no traction from what I remember

[Buster]

They also provide almost no traction from what I remember

That's OK for a Prius or Insight. I rarely see one going over 35 MPH. They're always holding up traffic around here. :D

Of course, it could be because they want to make sure everyone sees their "I love trees and you don't" stickers.

[LiveWire]

Make some "I love destroying the environment with batteries" stickers and put them on those cars in parking lots. :splitnana:

[phordzx2]

The additive you linked to sells for $50 a gallon vs. $9 a gallon for the 2 stroke oil.

Yup and you only use 2 ounces per tank. So its like .78 per tank. I've been using this stuff for years and its helped all my cars in the mpg department. Don't buy it though, I don't want there to be any more demand and the price go up. Last time I bought 10 cases for me and my family it was $20 a gallon.

[bcorradi]

I just picked up a 99' MTX ZX2 last weekend. I checked my mileage on the first tank after driving it extremely nice (keeping the rpms below 2500) and I averaged 36.1 mpg. This is with 90% highway and 10% city driving. I don't have cruise control, I didn't put extra air in the tires, and I'm currently running dino oil. I plan on putting mobil 1 synthetic in it this weekend and adding extra air to the tires before next week to see how much it improves. Are there any good sources for aftermarket cruise controls?

[Buster]

Make some "I love destroying the environment with batteries" stickers and put them on those cars in parking lots. :splitnana:

:D:dance:

[mechtech]

Cruise control is good for flat stretches, but will hurt MPGs in hilly areas.
M1 is on the thin side of it's rating, so you might see a .05% increase in MPGs. It is not slipperier than dino. It's all about viscosity.

[phordzx2]

FWIW, my 40.4 mpg and 39mpg run was on 5w20 motorcraft semi synthetic and the lube control stuff from LCD. I run the same tires as the hybrid honda insight, the re92 bridgestones. I have a 98 mtx zx2 so my rpms at 65 mph are right at 3000. I ran cruise on hills but coasted down the long ones where I could maintain speed or only drop a couple miles per hour or so. Keeping the rpms down will definately help, since those two runs I just bought the k&n stock filter and it seems to run better with it and hopefully we will see some long term higher mpg on average. It better, that dang thing was $42 at autozone, I'll probably have to run 100,000 miles to see that payback on investment. ;-) This may sound crazy but I only put enough oil in the motor so that its half way between low and high on the dipstick too (old habit from engine crankcases without windage trays).

In the future I hope to side gap some cheapo copper autolite plugs and degree them so that they are in the middle of the two exhaust valves as well as I have had luck with that in the past and also unplug the knock sensor.

[mechtech]

Phord - Don't waste your time with indexing the plugs. Filing the side electrode back [and rounding it] to flush with the center [still leaving the platinum intact] is a good idea. It helps flow in and out.
Clean your MAF with spray dedicated MAF cleaner after running the K+N. Oils and dirt will get on it. They flow a bit better, but DO let in about 3% more grit than paper, with concurrent oil problems. I use paper, and took my K+N off. It depends on where you drive. If it is dusty, use paper.

[ZX2_2008]

if i want to put the resistor on the maf harness which wire do i tap into
for a 98 four wire setup, cause the picture on here is a six wire setup

[gunman_sr5]

if i want to put the resistor on the maf harness which wire do i tap into
for a 98 four wire setup, cause the picture on here is a six wire setup

Either wire on the IAT.

[Tygen1]

Cleaning my K&N cost me 1.5 mpg, until I cleaned the MAF and throttle body, then I gained another 1 MPG over where I was. Definately had some oil tranfer to the MAF hot wires.

[tweakfreak]

Just for reference. Using my newly acquired ScanGaugeII I logged some fuel numbers. Driving the S/R from Chicago back to Detroit I tested various speeds and 40-50mi intervals. Granted this isn't perfect and its not a solid control I came up with the following numbers:

Temp= 85F, A/C on, car is packed(only room for the driver, back wheels are tucking) with my stuff because I am moving back home for the summer.

60 MPH = 46-47 MPG
65 MPH = 43-44 MPG
70 MPH = 39-40 MPG
75 MPH = 38-39 MPG - Outlier. Ran a couple times w/ similar results.

I found it harder to maintain a solid 75 MPH then other speed runs(traffic etc.), however the average IS 75 MPH on the last test. I thought it was interesting how the 75 MPH didn't decrease as much as the others. Perhaps the section of road I was running the last speed test on was at a general decline. In theory it should decrease exponentionally as air resistance increased. I understand that there are many variables that will play into fuel economy including rotation mass(axles, rims/tires etc.) I am thinking it didn't decrease as much as expected because the engine is starting to get into its peak VE(Volumetric Efficency) area. I wasn't watching the vacuum between these runs that would probably be a better indicater of why. The results will likely vary from other folks as I have some work done to the engine. My adjustable cam gears shift my VE around a bit as well as the exhaust work and the PNP intake manifold(very slight).

Note that this is on 93 octane, no additives, no resistor and no cruise control. The closed loop spark maps are from a LXQ1(01 MTX computer). I suppose I could of taken note of the spark timing, but varies so much based on elevation change its hard to make an accurate measurement on the freeway. The whole trip I averaged about 42MPG.

[mechtech]

47 MPG at 60 MPH with the AC on is hard to believe, for me.
Scan Gauge numbers will be useful for relative readings, but exact values are dependent on the inputs.

[ZX2_2008]

if i dont have MAF cleaner you can use brake cleaner right?

[JohnP]

The wifes Prius will run 50-52 mpg @ 70mph , 43-45 mpg @ 90-100 mph , tops out @ 117mph . Run about 5 car lengths(best spot) behind a semi and it'll get 60+ mpg @ 70 mph . Around town you can get 46-48 mpg . All the mileage figures are with the A/C on , it's electric ,not engine driven . With the Traction Control disabled it won't bog off the line , the 295ft.lb. torque from the electric motor it'll hold it's own with most cars in 60ft.

I changed tires to a LRR 190-60-15 600 tread wear run @ 42psi front/40psi back . Run a modified air box with a K&N filter and a cold air duct straight to the grill ,less then 20" . Added a little more to the front spoiler . All fluids are from Royal Purple .

The Prius is 100% recyclable , how do you recycle a tree once it's cut down . Theres a company called Hy-Motion that has a extra battery conversion to make it a plug in . With the extra battery the car will get a combined mileage of 100 mpg .

[SnowBoardinWNY]

I always saw this thread but always forgot to read it lol or click on it for that matter. I will go out and pick up a resistor tomorrow and put this bad boy to use. I will also try the oil in the tank I guess.

[Beodude123]

So the resistor thing really works? I might have to give it a try.

Does it give any extra power?

[tweakfreak]

47 MPG at 60 MPH with the AC on is hard to believe, for me.
Scan Gauge numbers will be useful for relative readings, but exact values are dependent on the inputs.

I would say its possible. I have powder's UDP, 0w-20 oil and all the breather mods working in my favor. The wide sticky Goodyear Eagle F1's don't help though.

Last two trips with that car I averaged 38MPG(the old fashion ways of measuring) doing 75MPH packed w/stuff and the A/C on. One of those trips was to PA two years ago for a ZX2 meet at Cyberman's. PA isn't exactly flat.

Does anyone recall the optimal IA temp for fuel economy? I am thinking its somewhere around 60F.

[ZX2_2008]

hey, mech. you say the k&n deposits oil in the maf.
is that with all K&N's drop in and universal?? and also
which is better for aftermarket intakes k&N or a foam filter??

[hollxiter16]

i did the resistor a couple days ago and wow does it work. i also added the 2 stroke oil and my engine runs a lot smoother. now i just need to throw in better injectors.

[mechtech]

the K+Ns won't hurt the MAF, but will coat it for bad readings unless it is pretty dry. Cleaning the MAF every couple of months or so is a good idea.
Paper has much more pleats, and filters better.

[so_slow_zx2]

hey Mechtech, Will either of these "mods" have any affect on passing emissions tests?

[SnowBoardinWNY]

if they don't throw any codes then why would they? My answer would be no they wouldn't effect your emissions but let someone else back me up. You'll be fine lol.

[ZX2_2008]

ok thanks, just wondering cause your running the stock airbox right?

[SnowBoardinWNY]

I haven't done it yet, just bought the resister today. I have other problems that need to be fixed before I do this though. It will not throw a code though.

[Stretch]

if they don't throw any codes then why would they? My answer would be no they wouldn't effect your emissions but let someone else back me up. You'll be fine lol.

Just because an engine isn't throwing codes it doesn't mean it's running efficiently and/or with little emissions. Plenty of cars out there are driven daily that go for an e-test and fail ..... no CEL present.

[mechtech]

No effect on codes or emissions.

[so_slow_zx2]

thanks guys

[RedRacer99]

does trac control eat gas? if so, i can switch mine off. any other helpful tips?

[Zx2 Frost]

We don't have traction control.

[Grommish]

Just because an engine isn't throwing codes it doesn't mean it's running efficiently and/or with little emissions. Plenty of cars out there are driven daily that go for an e-test and fail ..... no CEL present.

Only if your inspection station does a sniffer test would you fail a E-check without a CEL code (aside from the visual, if any)

Most places will just pull the ODB-II data

[00zx2s/r]

so i've gone two fill ups w/ the resistor and no change in mpg. I've even been driving the speed limit and accelerating slower and it's not doing much... I'm guna tear into my maf and make sure I have the right wire tho...

[Tygen1]

Hey Mech, do you think this would work on a 2000 Focus with a Zetec?

[LiveWire]

does trac control eat gas? if so, i can switch mine off. any other helpful tips?

I think it would depend on the implementation. If throttle by wire, I would think it would improve mileage because it reduces acceleration. If it applies the brakes, it would probably hurt mileage.

[mechtech]

Tygen - I dunno. It depends on if the IAT sensor is similar. It has to increase resistance as the temp goes down, and you would have to use a suitable resistor. I wouldn't do it unless you checked the values first - by a meter at different temps, or by a manual with exact specifications.

[Tygen1]

Of course, that would make sence :) Silly me... Thanks Mech. I noticed the Focus Zetec also uses a Knock sensor, hmm...
I thought my ZX2 was slow until we got a Focus, blah!!! It's a big time dog.

[Beodude123]

I think it would depend on the implementation. If throttle by wire, I would think it would improve mileage because it reduces acceleration. If it applies the brakes, it would probably hurt mileage.


From what I have read, reducing acceleration isn't really all that good. There is something called "hypermiling", which is basically getting the most MPG out of your car. Apparently, full throttle acceleration is most efficient. So reducing your power isn't really good, since it makes your engine less efficient.

[J_Mob]

Apparently, full throttle acceleration is most efficient.


Awesome. Good to know that I am doing something right.:lol:

[FatTonyZx2ner]

just filled last tank and added 4oz marvel to the tank. last tank was mostly city @ 25 mpg, this one i was at 240miles with more than 1/3 left on tank so we'll see soon.

[Boski]

with the resister mod and all my other mods if i drive to save gas i have been getting 29 ish from tank to tank. "city" i dont get to do much highway driving

[Stretch]

Only if your inspection station does a sniffer test would you fail a E-check without a CEL code (aside from the visual, if any)

Most places will just pull the ODB-II data

I was unaware that (some states?) only pull OBD-II data only.

Regardless, my point remains - an engine can run like crap with high emissions and still not throw a CEL.


EDIT - after re-reading this my last sentence may seem like i'm being kurt and rude. Apologies, i'm just being straight to the point. I don't mean for it to sound offensive.

[Tygen1]

OK, here's a couple pics of what I did. 5.6K Ohm resistor on DPST switch in a project box. You'll have to excuse the poor quality camra phone pics. I hooked it up to my Focus and will be doing a 1600 mile round trip next week. So I'll alternate on and off the resistor to see what difference it makes. I would have done it to the ZX2, but I'm not taking it on the trip. Consequently the Focus uses the exact same resistance values for the IAT, same color wire and same pin on the PCM. I'm sure the Focus is tuned differently from the factory, but it will be ineresting to see how this modification works on other Fords. It has a knock sensor also, but the Focus guys are not complaining about it. However I plan to put a switch on it also and see what's up for myself.
The ZX2 will get this next, but I was thinking of doing a POT and testing different resistance values to see what works best for my 80 mile commute.

[mechtech]

With a knock sensor hooked up, you may nullify any gains.
I'd unhook it.

[Tygen1]

I'll have to unhook the knock sensor on the trip back to see if there is a difference. Thanks for the tip :)

[RedRacer99]

oh well.. at my worst, i hit 24mpg, i usually average about 28 though which is much better than i got in the zx2. i averaged about 25 in that one

[gunman_sr5]

38.5 again on my last tank. I have a CEL now. I am guessing the resistor came loose. Gota check the codes in the morning.

[mechtech]

Next time use solder, not Play Dough!

[gunman_sr5]

Its held twisted into the wire and heat shrink for 5k miles. No biggie it was a simple fix.

[Stretch]

So mech, for those of us with our own EEC tuning capability, would it be fair to say that this can be duplicated in a tune by adding "5" to the appropriate column for the AIT/spark scalar? (sorry, I don't know what the actual tag name is as I have yet to receive my Advantage 3 upgrade and it's labeled different for different strategies)

[jombee]

Just put the resistor in.
Very simple to do, it really is as easy as

1. cut wire
2. strip ends from wire
3. wrap wire around both sides of resistor
4. wrap tape around the whole thing.
5. wait to see if any difference
6. solder current connections.

[cone-cerned]

I just finished driving 1320 miles, mostly with A/C on (yea Texas), put in 36.36 gallons of gasoline giving me 36.29 mpg. I have my Kumho MX's, 205-50/15 tires aired up to 40 psi. Next, I am going to change to 195-60/15 Yokohama Avid Touring inflated to 40 psi. and then drive another 1200 miles. I plan to add the resistor after that.

[mechtech]

Stretch - I am not conversant in your specific tuner.
But adding a bit of ignition advance is what we ultimately want.
Whether we twist a distributor, cheat and fool the computer, or program it.

[dohc v6]

So if I put the resistor in, I should disconnec the knock?

[Grommish]

So if I put the resistor in, I should disconnec the knock?


You should disconnect the knock sensor even if you don't put the resistor in..

[mechtech]

ditto grommish
But be prepared to go up a grade in fuel, like 89 from 87. It may or may not be needed, but in real hot weather you may need it. It is worth it, so don't sweat the extra $ per gallon.

[Stretch]

mech - fair enough. I figured as much. I'll be sure to have fun playing with this and the knock sensor. :biggrin:

[Tygen1]

Ok, averaged high 28 mpg on the trip out. Not impressive at all. I tried to keep the speed between 70-75 mph because time was more important than fuel cost. I didn't switch the resistor off, but will try that on the return trip. The Focus averges 23 mpg in the city, so 28 highway seems in line with that. It is so much weaker than the ZX2 that it isn't even funny. The ZX2 has taken this trip many times and averaged 34mpg under the same average speeds and has way more gitty up.

[RedRacer99]

focus isn't a very light car for its size

[RedRacer99]

consider our car an s10, the focus is the suv version "blazer".

[Buster]

consider our car an s10, the focus is the suv version "blazer".

Ummmm....yeah...

[Tygen1]

It may be fat and slow but it will outhandle my ZX2 by a large margin :)

[Tygen1]

Ok, looks like the resistor helped by 1.5 mpg. I need to mess with the resistance some more to see if more is better.

[mechtech]

Leave it alone. All the thinking has been done for you.

[Beodude123]

Hey Mech, where would I be able to pick up some aluminum sheet? The only thing I saw at Lowes was some PVC type clear plastic sheet, about 1/4 thick. They had a sheet that was 12X36 or something like that. I think it would be too skinny for the car.

Do you have a picture of where the good spots would be to cover up? I want to figure out how to smooth everything down there. There are a couple of spots I want to know a bit more about; IE the wheel wells and the exhaust area.


I am interested in doing this stuff, just to see what I can get out of the beast. I plan on getting a couple of resistors tomorrow, and I want to pick up something to smooth the flow underneath the car.

[Tygen1]

Wait....I'm still thinking.... :)

[RightMarc]

Wow this mod really works doesn't it? I filled the tank up on Friday and just did the sensor mod this weekend. I am now at 60 miles and the gas guage is still touching the full mark. It's usually down below at least 1/8th tank by 60 miles. Scangauge surely enough is showing about 8 degrees less intake temperature than the actual outside temp, yet it's indicating I'm getting the usual city gas mileage of 34mpg. So, I won't know for sure how much mpg I'll be getting until next time I fill up though. So far so good.

Mechtech you're a smart guy. That remark about Biafra had me chuckling. I had to look up that it is a secessionist state in Nigeria.

However, getting the knock sensor off was a hell of a struggle for such a seemingly simple task. It helps to have good hard tools. I don't. I wrecked two sockets breaker barring the cross member bolts off.

BTW what happened to my account?

[Buster]

The site crashed and everyone lost their accounts.

[Tygen1]

So I did the IAT/CTS "Pots mod" to the ZX2 over the weekend. Marked 5K ohm on the project box. Filled up last night, did my usual 80mile commute to work and back, then filled up again. I am very impressed at the gain. 3 mpg so far. I do a 50/50 mix of highway and city and on the highway I drive 70mph. Today I only did one WOT run to pass a semi that cut me off. So I'm betting tomarrow will be a little bit better. Oh yea it was approximatly 70 degrees in the morning and 90 in the evening and I was running my AC. I got 34.2 mpg today, that's what I used to get on the highway stock. :)
Someday, I'd like to shake Mech's hand and thank him.

[mechtech]

Just make sure you grab my hand... not some other appendage!

[Beodude123]

Mine doesn't really seem to be helping gas mileage... It definitely gave me more power, but the mileage doesn't seem to be there.

It was weird, right after I did the mod, I turned the car on, and I can kind of smell gas in the car, it's coming from the pump area. Why is that? I never smelled it before...

[mechtech]

If you smell raw gas something is wrong, and your mileage should improve when you identify it and fix it.

[koihoshi]

I'm getting between 35-43mpg lately.

[mechtech]

koi - Where have you been hiding?

[OEM project car]

K well I just bought a 98. On my first fill up I got 300 to 10 gallons, I thought that wasnt bad. well I did some tune up stuff, wires plugs, fuel filter, pcv, tranny filter top o2, and now I am only getting around 240 to the tank ... ridiculously low.
Mech it seems as though you know a lot about these things. Can you think of what my problem is? I am not showing any codes.

[Zx2 Frost]

what wires, gap plugs? what kind of plugs

[koihoshi]

koi - Where have you been hiding?

Everywhere lol.

[OEM project car]

what wires, gap plugs? what kind of plugs

ford racing with oem autolites. I did the resistor mod and didnt see any gains in mileage. I just filled up again, i went 61 miles on 2.08... so around 30 with a lot of 55mph on highway. There is def something wrong. I had a buddy ride in the car that had a 98 atx and he said the car felt slow. Could there be something else I am missing? I just dont see how you guys are getting around 40, I mean I am so far off ... any help would be appreciated.

[tweakfreak]

I just did the Chicago run Friday morning. I averaged 44.9MPG@60MPH, this includes some stop and go in the city. I had the front side windows down only about 2" and the fan motor blowing air through the vents(no A/C) to make a good draft. I used my scangaugeII to monitor everything most of the way. Here are the specs for reference:

2003 Escort ZX2
32K miles
Automatic
Intake and Cat-Back
IAT = AVG of 85F
Top speed of 60MPH@2280RPM

-----

There are many variables that will determine the most fuel efficient speed and it does vary from different vehicles. Generally though 50-60MPH nets the best fuel economy on most. For manuals I found the tallest gear and the slowest speed possible nets the best fuel economy. Granted crazy camshafts and what not will play w/ your VE(Volumetric Efficiency) and shift this around. Autos are similar, the tallest gear w/ torque converter lockup and the slowest speed net the best fuel economy.

I wondered about the windows vs. a/c debate. This does vary based upon vehicle because the compressor load, belt speed etc. changes everything. The ZX2 mentioned above has the factory A/C and factory crank pulley. The few miles I tested engaging the A/C vs windows@60MPH I found that windows generally won. In the ZX2 you can physically feel it engage, TPS increases considerably and MPG dropped when doing 60MPH on a flat surface from 46-47 to 41-42MPG. This relationship gets more favorable to A/C as speed increases due to the law of aerodynamics... maybe 80+MPH the lines cross, however, the compressor will be rotating much quicker... the rotational mass will be a killer at a fast speed. Also, at a stop while in the Drive gear the car uses 0.22GPH(gallons per hour) w/ no A/C and .0.33GPH w/ A/C.

Take it all with a grain of salt but I say the results are generally convincing that slowing down to 60 and keeping the A/C off are very favorable for fuel economy. What percentage increase you receive will vary depending on your vehicle(VE curve, rotational mass, drag coefficient, gearing) . The big problem driving slower was the big trucks passing(rocks) and having to get over for merging traffic. The trip doesn't really take that much longer and you often find yourself seeing the same people pass you two or three times.

Comments, questions? Tomorrow morning I will be making the same trip... I'm contemplating another trip @ 60MPH or 55MPH. In some brief testing in my 5spd manual ZX2, every 5MPH lost me 3MPG(according to the scangaugeII).

[OEM project car]

Well do you have any suggestions for my crisis. I forgot to mention that I have also unplugged the knock sensor.

[tweakfreak]

Well do you have any suggestions for my crisis. I forgot to mention that I have also unplugged the knock sensor.

If everything is operating correctly its either where your driving(temp, elevation, A/C, city vs freeway) and your driving style.

I did 55MPH w/ no A/C from Chicago to Detroit and managed 49.7MPG.:monkeybutt:

[iceracer]

Found a couple of interesting web sites: www.cleanmpg.com gives mostly driving hints.
www.ecomodder.com deals with aerodyamics etc. and othe mods to improve mpg.

[Stretch]

Mechtech - more questions for you (or others that may know), if you don't mind please. I'm not trying to hi-jack your thread - I am sticking to the same theory you start with for increasing mileage. If I may .....

While I do realize that having a car with a DOHC engine already lends itself, for the most part, to having an engine that favours high-rpm operation (at least from an efficiency perspective - which is what this thread is about), i've been trying to look into boosting the Zetec's lower rpm efficiency, where I drive most. I'm thinking that the following would be a good recipe, with "minimal" cost (subjective, of course);

Keman intake mod (stock air filter)
adjustable cam gear (to advance intake only, i'd leave VCT intact and operational)
SCT tune (obvious reasons)
exhaust (all of it LOL! ..... ???)
intake manifold porting
mill head (CR bump), p'n'p on runners (need more research here on both)

Is there anything else you'd recommend that is "minor"?

As much as i'd love to add cool wheels and a body kit I know these won't help the cause, so i'm leaving my swirlies in place. Previous owner put 195/60-15 tires, which i'll probably put stock sizing back before winter. Hard to justify lighter wheels, but might if they REALLY help. :?

PATIA! 8)

[tweakfreak]

You could slam the car. I'll be doing a more controlled study of mech's resistor mod in the next coming weeks I hope. In theory it makes sense however I'm not sure if I'm sold... sorry mech :)

[OEM project car]

Ok so I am running down the list of things that can affect gas mileage. Just to clarify ... I drive with a very soft foot never accelerating over 2800-3k on. I drive around 20 miles per day all city with moderate traffic during the morning. When I bought the car I drove it about 100 miles highway home then the rest city getting 300 to the tank. Since then I am experiencing around 25mpg. The 300 mile tank was on an old neglected car with bad plugs, a clogged fuel filter a never changed tranny filter. After that tank I did a tranny flush, changed pcv, resistor mod, knock mod, top o2 sensor, fuel filter new ford plugs ford racing wires and now an MMI intake from little bro.
What are the other items that can be affecting gas mileage? I also have no codes.

I need some ideas so that I can look into it further so I can start getting the gas mileage I bought the car (like a clogged exhaust system, bad temp sensor, ...) or is it just that the car only gets this kind of mileage?

[ZX2_2008]

is this safe on an S/R sence the timing is already advanced on the PCM