15 40 is probably too heavy for your neck of the woods.
high idle cold
Thread Starter
Cruising
Joined: Dec 2009
Posts: 10
Likes: 0
From: Odenton Maryland
high idle cold
Here is one for you all. My 87 has started to act up. It will idle 500-600 RPM cold and stumble. As it warms up the idle increases. When fully warm it idles 1600. I have check and repaired vacuum leaks. It was intermitent for a while. If I disconnected the battery to clear the ECM it would be fine,now it is all the time. Idle Air Motor?
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Joined: Oct 2007
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From: So. Cal.
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Vette
Here is one for you all. My 87 has started to act up. It will idle 500-600 RPM cold and stumble. As it warms up the idle increases. When fully warm it idles 1600. I have check and repaired vacuum leaks. It was intermitent for a while. If I disconnected the battery to clear the ECM it would be fine,now it is all the time. Idle Air Motor?
Mike
Thread Starter
Cruising
Joined: Dec 2009
Posts: 10
Likes: 0
From: Odenton Maryland
We bought the car in March '09 , changed the oil right away I believe I used 15/40 . We don't drive it in the winter. I never changed out the IAC motor. The air filter looked almost new.
Team Owner
Joined: Jan 2009
Posts: 73,568
Likes: 33
From: Somewhere in Mo
St. Jude Donor '09-'10, '14
Take the IAC out and give it a good cleaning with carb cleaner. Also clean the throttle body good. That is a no cost test and should give you an idea if it is bad. Don't assume it is the IAC until you try this.
Team Owner
Joined: Jan 2009
Posts: 73,568
Likes: 33
From: Somewhere in Mo
St. Jude Donor '09-'10, '14
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