QuestionQUESTION: WHAT SHOULD THE IDOL BE SET ON?I JUST CHANGED THE IAC AND WANT TO KNOW IF IT IS SET RIGHT.
ANSWER: The IDLE controls are set by the computer, once the I.A.C. is installed. The ECU (engine computer) takes readings and adjusts the idle with the IAC valve/mechanism. The engines computer usually runs the engine smooth and steadily somewhere between 550 and 1000 rpm depending on which motor, year, model, etc.
One thing is for sure that it should not vary more than 100-200 rpm once the engine is warm otherwise the T.P.S. (Throttle Position Sensor) may need to go through an adjustment procedure. Can I ask why you needed to change the I.A.C. in the first place? Was the Idle acting erratic? Revving up and down from 800-1500 and back? Also, Let me know about what year, make, and model we are working with! Thanks.
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QUESTION: I have a 2002 galant 4 cyl.It has been giveing me alot of problems with idleing.I replaced battery,relay,throttle position and now iac.When we would crank it it would die if you didnt press the gas.After i put throttle position on it it would crank,but when stopped at red light and fan came on idle would go down and light came back on.The code was always 507.I hope it fixed my problem.Now i got it back when i crank it the idle goes up to 1500 and then comes back and sits around 800.Is that good?
AnswerYes! That is very good. That is exact-ally how is is supposed to start and idle. And is the idle smooth? As in does it sit pretty steady at 800 +/- 50 or 100. If so, then you are in excellent shape, and finally have fixed your problem. I am willing to bet that the IAC was your problem in the first place, but sometimes problems like that can be hard to diagnose. There is a way to test the resistance of the TPS sensor to tell if it is bad or not... but since it has been replaced you know that it is good. I'd like to know how it runs now that you got the new IAC installed!
