IAT Sensor Mod Experiment

[SVOboy]

I put together my 110ohms and stuck them in the IAT, and will begin testing tomorrow, hopefully I'll get some good results, and throw up a picture of the stuff.

[SVOboy]

This is what my set up looked like, smelled like hell, undid it, smell went away. Obviously it is no good for my damn engine, but as larry has done it on his, and flatland on his, it isn't bad for everyone's.

[Scorn]

The idea behind this mod is to trick the ECU into thinking that the air coming in is the perfect temperature so that it gives a better air/fuel ratio. Considering all cars are different, and all AIT senseors are different, the size resitor that you use on your car should be for your car only. The way to test and see what kind of resistor to use is to check the reading coming from the sensor with an ohm meter on a day when the temperature is nice and the engine seems to be running better because of it. Whatever reading you get is the size resistor to use, and you only need one.

[SVOboy]

Yep, that's true, but a lot of cars within the same make share resistors, for example, all obd0 and obd1 hondas use the same stuff, and the reason I used two resistors was because I ran them in parallel to halve the resistance of a single resistor, which gave me the proper resistance in the end.

[SVOboy]

Yep, so I got a different kind of tape, threw the resistors back in, no stink!!! So this test is back on, hopefully I'll find some good stuff out in the next few fill ups.

[GasSavers_Explorer]

I've been doing a little looking around on the net at some different websites that explain the theory behind using the resistors. I'm not sure if you guys are only trying this on the passanger cars or not, But in my findings I found that on my particular SUV (99' Ford Explorer XLT 4.0L) that the resistors that most people are using, uses a resistance value of 3,300 ohms to override the sensor and signal the computer that it is receiving air at an optimal temperature of 58 degrees. this info was found on an EBAY ad claiming to performace increases of up to 20HP. One question i have is first wouldn't this end up hurting your overall gas mileage conciderig that your letting the injectors stay open longer spraying longer? and second question is exactly where do these resistors plug into? Do they plug into the harness going to your MAF? I'm kind of new to the whole boosting Hp using resistor's only reason i'm pursuing this method of performance tuning is i'm not to ready to drop $800+ on a programmer for my truck yet. Any additional info would be appreciated. And thanks for having me in the forum.

[zpiloto]

I tried this IAT mod with no increase in FE. Tried it with IAT temp reading 240 and also 160 (according to the scan gauge) with no increase. I think the ECU changed the timing thus netting no result.

[SVOboy]

We're doing the resistors for fuel economy. As stated for some people it works and for some people it does not, depending on how the car works. Resistors are a ****ty way to get power, and will kill gas mileage if you try.

[Matt Timion]

Originally Posted by zpiloto

I tried this IAT mod with no increase in FE. Tried it with IAT temp reading 240 and also 160 (according to the scan gauge) with no increase. I think the ECU changed the timing thus netting no result.

It looks to me like Casper is obd2, which most likely has variable timing. I believe this modification only works on obd1 and pre-obd cars.

[diamondlarry]

It seems to work on my OBD2 '97 Saturn. My air temp is reading 247 degrees F. As for timing, it seems to run as high as 39 degree btdc which is about where it was before the mod.