Normal idle for a '93??
Thread Starter
Racer
Joined: Apr 2005
Posts: 484
Likes: 5
From: Madison Wisconsin
Normal idle for a '93??
Every since I've owned my '93 (about 7 years and 44K to now 93K miles), it has exhibited what I'd consider a high idle. When I take my foot off the accelerator the engine will drop to 1,000 RPM. After sitting awhile at stop light it will drop slightly to about 900 RPM. I tried one tip on the Forum about resetting the IAC, (starting engine, unplug IAC, shut off engine, remove key, plug in IAC, and restarting engine). When I did this the engine dropped to 600 RPM and idled well, but as soon as I accelerated, the idle went right back to 1,000 RPM.
Is this normal and if not, any thoughts on a possible cause?
Thanks,
Jim
Is this normal and if not, any thoughts on a possible cause?
Thanks,
Jim
Safety Car
Joined: Aug 2002
Posts: 3,842
Likes: 230
From: SANTA CRUZ CA
Every since I've owned my '93 (about 7 years and 44K to now 93K miles), it has exhibited what I'd consider a high idle. When I take my foot off the accelerator the engine will drop to 1,000 RPM. After sitting awhile at stop light it will drop slightly to about 900 RPM. I tried one tip on the Forum about resetting the IAC, (starting engine, unplug IAC, shut off engine, remove key, plug in IAC, and restarting engine). When I did this the engine dropped to 600 RPM and idled well, but as soon as I accelerated, the idle went right back to 1,000 RPM.
Is this normal and if not, any thoughts on a possible cause?
Thanks, Jim
Is this normal and if not, any thoughts on a possible cause?
Thanks, Jim
Melting Slicks
Joined: Mar 2008
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From: Delta B.C. Canada
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If you do pull the IAC, take off the throttle throttle body, and give it a good cleaning. That includes the air orifices to the IAC.
FWIW, I had the same high idle in my 92, and that was only resolved after the ECM was repaired for another issue.
FWIW, I had the same high idle in my 92, and that was only resolved after the ECM was repaired for another issue.
Thread Starter
Racer
Joined: Apr 2005
Posts: 484
Likes: 5
From: Madison Wisconsin
Thanks for the tip. I cleaned the IAC, and throttle body, then reset the IAC. I drove the car for a few minutes and the idle was right around 700 RPM. After letting the car sit for about 45 minutes, the idle is back to 1,000 RPM. I'm thinking it might be the IAC itself. I can pick up a Delphi unit for about $62. Might be worth a try unless any others have some suggestions.
Thanks again,
Jim
Thanks again,
Jim
