I have a 91 stealth r/t that was idling at about 2100 rpms, ardered a new iac, installed it this morning, and now it idles at 3000 rpm's! Anyone have any ideas?

 

Someone may have adjusted the Fast Idle Air Valve or the throttle stop to compensate for a bad IAC or ECU. Try those first and if that doesn't improve the idle it may be the ECU. There are some places that will test the ECU for free and repair if needed.

Let us know what you find.

 

It was the throttle stop screw ran all the way in! Adjusted it and it idles great now! Thanks for the help