My car idles at 1500 and wont drop down. I have replaced the TPS and cleaned the throttle body hoping that would help, but it didn't. Maybe I should replace the IAC. I have the idle screw backed completely off the screw and the idle wont jump down. I found a vaccum leak up by the two relays on the firewall and plugged the leak and that didn't help either? I have searched many times for a vaccum leak, but can't find any. Sometimes the car will idle to about 1100, but then jump back up to 1500. If replacing the "Idle Air Conrol" valve would help, please let me know the procedure of installing it so it wont break. I have looked for this topic but the search is down at the moment. I have sorta asked this question before but now the car is hard to drive when it idles at 1500 or so. THANKS FOR ALL INPUT.

 

Follow the procedure for setting throttle minimum air position. That should identify whether the IAC is a problem or not.

 

if the problem is due to the iac, should it be cleaned or replaced? im having a kind of similar problem, just not as extreme.

 

I replaced the IAC and the TPS a few days ago. Strangely enough it didn't work at first. When I started it, it would again idle high. Then after driving it around for awhile it would eventually idle down. But, it still idles at about 1500 for about 10 seconds right when started, which I think it too long. I also cannot adjust the TPS within specs. I cannot get the voltage to read 0.54 volts with the key on. The best I can get it to read is 0.43 volts with key on. I think the car is supposed to idle at 500 RPM's in gear, but the lowest I can get it is 700 or 750, why is this? Are there any tricks to adjusting the TPS and getting the idle within specs. The car stutters when I give it gas and I just assumed it was due to the TPS not being adjusted right.
----------
Also, what are the procedures for setting throttle minimum air position? And after doing that, how does that determine is the IAC is at fault? THANKS

 

I also chasing same issue,used the smoke machine to get a better hunt on the vacuum leaks,but only leaking around injector o-rings a little,just bought a Wells IAC and it definitely made it worse?????put the original back in it,gonna chase this some more,but the miniumum air adjustment is to no effect,there must be something obvious i'm overlooking?

 

Post if you figure something out. I'm gonna check for ECU grounds and then test my coolant temp. sensor. Let me know.

 

The car when first started idels at around 1500 rpm i dont know of much t/a's or camaros that dont. i've had 4 t/a's and they all did that then after 1 or 2 mins they would go back to normal and idel fine. as for the 700 to 750 idel in drive check your timing and if the tps is set right you might need to get a new one i have to change mine twice before they go bad.