I have an 88 4 cyl 5spd and I am having a problem with my idle. Sometimes but not always when I start it up the idle speed goes to 2000 and even when warmed up does not drop down to 1000. When it starts if the idles is normal it stays normal when running. When it starts to a fast idle it stays that way until it is shut off and restarted. Is that understandable? Anyway does someone have an idea on the problem?
Thanks for any help.
Jon Steckelberg

Not alot of info to go on, but sounds like a sticking IAC valve to me.

Phil

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GTDude
OVER 25 years GM experience

What GTDude said....also, check all your lines for vacuum leaks!!!!!!

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The force will be with you, always.

Well as far as more info goes. The car has 125,000 miles on it. I have only owned it for 5 months. It was well cared for by the previous owner but I have no maintenance records. Most of the components in the engine bay look original, ie sensors. There have been no "modifications" to the car. The problem begins when I start the car. Some times when I start it it has the high idle sometimes it does not. If the idle starts normal it stays normal if it starts high it stays high until I shut it off and start again.
Thanks for the advice I was wondering if it could be the IAC. Is there a way to test this?

First thing to do is to try to clean the IAC valve.......remove it and clean it and the bore that you removed it from with throttle body cleaner. Also, clean your throttle body with a spray cleaner as you fluctuate the speed of the engine to clean the carbon built up in the TB.

Phil

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If you find my replies helpful, please take the time to give me a positive rating. Thanks.
GTDude
OVER 25 years GM experience