High idle issue
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High idle issue Been searching for a while and can't seem to solve my issue. Car is a 97 trams am lt1/a4. Mostly stock other than 3.73 gears. Car was tuned by solomon in January and have been having idle issues since. Started out idling a couple hundred higher than supposed to now its idling a 1500 in park and 850 in drive....supposed to be 650 in drive and 850 in park. Replaced IAC since the old one was seized up. No change at all. Have searched for vaccum leaks and can't find any. TPS voltage is within spec, map and maf sensors appear to be functioning correctly. Current codes are p1509 (reason for iac replacement) now I'm getting p1133 and p1153. I may have a small exhaust leak I have not confirmed it yet. Could that leak cause it to run high like this? Every other vehicle I've had an leak before the o2 on would run rich and all but die out. I don't have a can tool capable of checking the iac count. Any help would be appreciated.
Joined: Nov 2001
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From: Schiller Park, ILL Member: #317
An exhaust leak can't possibly cause enough extra air to enter the engine to bring idle speed to nearly double what it's set for.
The fact that all of this began right after a tune would lead me to believe that the tune is suspect, but if the old IAC was not functioning and there is no change with a new one, then it sounds like the new one is also not functioning. Perhaps a wiring issue? Perhaps a massive leak around the IAC?
The fact that all of this began right after a tune would lead me to believe that the tune is suspect, but if the old IAC was not functioning and there is no change with a new one, then it sounds like the new one is also not functioning. Perhaps a wiring issue? Perhaps a massive leak around the IAC?
