What resistor do I need to pull 6 degrees of timming?
that's good.....so it sounds like the resistor will pull the correct amount of timing when the car is retuned and set up for that in the tune. And if it is set up a little on the rich side the most i would give up would be a little performance with a open loop speed denisity tune correct?
closed loop speed density is what you want
setting up open loop as a little rich, still doesnt help if its not tuned on your leanest day
tune the car on a hot day, leaving it a little rich, and when it gets hotter, your closed loop tune will still add a little bit to the tune
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Teching In
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I'm wondering since the IAT sensor circuit shows the coolest air temp when the IAT sensor is unplugged witch equals the highest resistance and as it gets warmer the resistance drops and when the resistance gets low enough the PCM pulls timing. So I'm wondering if the 2 wires going to the IAT were shorted would the PCM read this as a high temp and pull the maximum amount of timing that has been programed into it. If so I could program the PCM to pull 6 degrees of timing when I flip a switch and short the IAT right before I spray the 150 shot of nitrous. Has anyone ever tried this? Or could this damage the PCM if attempted?
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Teching In
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I have done some more research. I have found out that using a 3 amp fused jumper wire to bypass the IAT at the IAT plug is a part of the IAT circuit test procedure. So doing this should not damage the PCM but it will set a code. I was able to find an post from 2003 that covered this topic. The result was use a 330 ohm resistor that tricks the ECM into seeing a 80 degrees Celsius or 176 degrees Fahrenheit and then reset the cells to pull the amount of timing desired.
