high idle

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Oct 22, 2005 | 06:47 PM

kjg26

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From: Alpharetta

high idle

HIGH IDLE! where is the adjustment screw?

keith

Oct 22, 2005 | 09:37 PM

mattd95363

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Joined: Oct 2004

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What engine? What year? The ECM adjusts idle. Perhaps you have a bad vacuum leak somewhere? What did you change? If you MUST adjust the base idle, it is a screw with a bolt head that is on the throttle body. It will probably have paint on it. If you back it out, don't back it out so far that your throttle plates contact the throttle body bore.

Oct 22, 2005 | 10:03 PM

quicklook2

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Joined: May 2004

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From: Lakewood, Ohio

idle air control is dirty or bad.

do not mess with idle screw.

Oct 22, 2005 | 11:11 PM

pfogle

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Joined: Feb 2003

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From: Oak Harbor, OH

There is a simple test to see if the IAC is working. Pull the electrical connector off. If the idle drops then the TPS is bad.

Oct 23, 2005 | 06:10 PM

kjg26

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From: Alpharetta

sorry for the lack of info. it's an 89 f150 with a 5.8L EFI.

Jan 17, 2006 | 02:37 PM

natewill

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Joined: Jul 2004

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From: Vincennes, IN

Quote:

Originally Posted by pfogle

There is a simple test to see if the IAC is working. Pull the electrical connector off. If the idle drops then the TPS is bad.

I too now have the high idle. I pulled the idle harness, and the rpm's dropped to around 1200 from 2000 or so. Does this mean that the TPS is bad? Are we sure about this??? I cleaned the IAC valve (and the IAC) with throttle body cleaner last night, and it made no difference. I HATE to buy parts until I find the right one...gets expensive really quickly!