1993 bonneville high idle

1993 PONTIAC BONNEVILLE
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IHRKE442
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I have a 1993 Bonnevile with 150,000+ miles, 3800 engine. It started to stay between 2000 and 2500 rpm at idle, it only does this after the car has been driven for 15 to 20 miles. I checked the linkage, all good. Throttle is at the idle stop. Can you point me in the right direction on where to check next??????
Sep 10, 2007 at 10:43 PM
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SERVICE WRITER
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You may want to remove and clean the idle air control motor. Carbon build up does strange things like this. Are there any codes in the computer or a check engine light on?
Sep 11, 2007 at 8:17 AM
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IHRKE442
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[quote:5ac0414cc0="Service Writer"]You may want to remove and clean the idle air control motor. Carbon build up does strange things like this. Are there any codes in the computer or a check engine light on?[/quote:5ac0414cc0]

no constant lights- SES came on & went off a couple times, I dont have a code reader. I assume the control motor is on the air intake?
Sep 12, 2007 at 9:07 PM
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Right, at the throttle body more precisely. Getting codes would certainly help... When the part is off, make sure the passageways are also clean. Get some good intake cleaner and spray it until it's clean. The pintle especially so it seals right.


https://www.2carpros.com/forum/automotive_pictures/30961_iac_3.jpg


https://www.2carpros.com/forum/automotive_pictures/30961_mitchel_12.jpg


https://www.2carpros.com/forum/automotive_pictures/30961_iac1_1.jpg

It wouldn't hurt to clean the throttle body and intake valves as well, but I doubt a relationship to your problem. The egr valve may also have some carbon issues as well as it's passageways.
Sep 13, 2007 at 4:56 AM