High Idle Issue
Thread Starter
Staging Lane
Joined: Feb 2007
Posts: 96
Likes: 0
From: Nacogdoches, TX
High Idle Issue Just picked up a '94 Z28. Car is an a4, engine is stock as far as I can tell. Only mods are CAI with a de-screened MAF, cat removed and a flowmaster welded on stock cat back.
When I start the car, it revs up to approx. 1800 RPM and hangs there for 5 sec or so then slowly idles down to around 1k. While in gear the car idles at 800-900.
I have checked all the vacuum lines and replaced all that needed it. Replaced the IAC, optispark, plugs, wires and set the TPS to .67 volts.
I'm thinking that the previous owner turned the throttle stop screw to compensate for low rough idle because the car needed a tune up. Car runs great now other than the idle issue.
What else do I need to check?
When I start the car, it revs up to approx. 1800 RPM and hangs there for 5 sec or so then slowly idles down to around 1k. While in gear the car idles at 800-900.
I have checked all the vacuum lines and replaced all that needed it. Replaced the IAC, optispark, plugs, wires and set the TPS to .67 volts.
I'm thinking that the previous owner turned the throttle stop screw to compensate for low rough idle because the car needed a tune up. Car runs great now other than the idle issue.
What else do I need to check?
