I know that this can be done but i was wondering if anybody knows of the sepectrum of resistance across the temperature sensor so i could find a variable resistor to control the A/F ratio. If nobody knows i can do the research myself and then give you guys feedback but it'd be easier and cheaper if someone already knew.
Air Temperature Sensor Mod
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So how do u do this mod? Which wires are they and which resistor do i need?
The Air TEmp Senor is on the air box on my 1999 taurus SE 3.0L Duratech if you pull off the sensor there are two leads for the sensor to hook up like a wall socket w/ no ground. If you place a resistor across it you can control the A/F ratio. As different temperatures of air move across sensor the resistance changes. So if you put in one resistor its tells the computer a fake temperature and changes the A/F ratio accordingly. I believe the lower the temperature the higher the A/F ratio and the more advanced the timing, which is desired for someone looking for performance. I see these things for sale on ebay all the time.
actually there called pots poteniomerters cant spell it but all it does is tell your motor the air is cooler and advances your timing but i would not do it. plus you only have them on when you race or your computer will firgure out what your doing a fix the problem. it will make your car faster. if you want to go fast with a taurus get a sho or run a 40 shot of nitrus wet your motor can take it as long as you dont spray all the time.
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·Let me stop you here, before you waste your time and money. The IAT senses the incoming air temp (self explanatory). These readings are used to adjust timing advance, fuel mixture, etc. By putting a resistor in, it's supposed to make the computer think that the air is cooler, therefore allowing the timing to advance more, and a richer AF ratio.
Here's some scenarios for various cars:
Cars with knock sensors (SHO, Duratec and FFV Vulcans)- if timing is advanced too much for the engine's current operating condition, the knock sensor will pick it up, and cut back timing. You've just defeated your purpose.
Cars without knock sensors: (Vulcan) - Since there's no knock sensor, the timing is advanced based on the IAT signal. Advance it too much, and detonation will occur.
Running a richer than required fuel mixture will hurt performance, mileage, and cause faster breakdown of the oil, as well as many other things. Fuel mileage will suffer, and honestly, you don't gain diddly.
Here's some scenarios for various cars:
Cars with knock sensors (SHO, Duratec and FFV Vulcans)- if timing is advanced too much for the engine's current operating condition, the knock sensor will pick it up, and cut back timing. You've just defeated your purpose.
Cars without knock sensors: (Vulcan) - Since there's no knock sensor, the timing is advanced based on the IAT signal. Advance it too much, and detonation will occur.
Running a richer than required fuel mixture will hurt performance, mileage, and cause faster breakdown of the oil, as well as many other things. Fuel mileage will suffer, and honestly, you don't gain diddly.
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Also, the O2 sensors determine the final A/F ratio once they heat up, thereby negating the effects of the mod. Iv'e already tried it. I used a 5.6K resistor. You can put it on either side of the sensor, it has no polarity.
The IAT sensor is a ceramic thermistor, not a potentiometer. The TPS is a potentiometer.
The IAT sensor is a ceramic thermistor, not a potentiometer. The TPS is a potentiometer.
Well regradless i did it today. First i made an exel graph of the resistance VS air temp. got a equation for the line (because it only goes to 60K ohm and 50 F) . I did some math like P=v^2/R<<<.25 watt much larger than need which is good. I then checked my AIR temp sensor with a multimeter, both the resistance and voltage at room temp it read the same as the chart next i grabbed and assortment of resistors .25 watt (wicked cheap in cost) I placed from 60Kohm all the way to 100Kohm and the higher the resistance i went the more power the car got it was noticable from a start bottom end increased a lot top end is same, also noticably throatier in sound. I didn't get any knocking(I run only premium gas) but some bogging noise at low RPM but power wasn't lost while the bogging occurred. I don't plan on running my car with this mod all the time. I'm going to make a switch or switch and knob, so i can bring it to regular air temp sensor during regular use. This does hurt gas mileage by about 5% approx.
So 60K-100K ohm resistor did the trick for me
So 60K-100K ohm resistor did the trick for me
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I hate to be blunt, but anybody who does this mod is just about plain dumb.
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