IAC - Idle Air Control & High Initial Idle
Thread Starter
Racer
Joined: Jan 2005
Posts: 418
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From: Houston Texas
IAC - Idle Air Control & High Initial Idle
General theory question regarding the IAC.
Generally the IAC allows some extra air past the (almost closed) throttle plate to increase the idle on a cold engine. When the computer senses the engine warming up, it closes off that extra air. (Am I correct so far...?).
I understand the IAC is a stepping motor. If the pintle and seat are clean, the EGR clean, and no vacuum leaks, what would cause the idle to run high (2500+) for about 3-5 minutes before settling down to a normal idle?
I suppose the theory would apply to most fuel injected/computer engines, but this particular motor is a 1990 Suzuki/Geo 1600cc that just had a valve job.
Any help, thoughts, advice, etc. would be appreciated.
Generally the IAC allows some extra air past the (almost closed) throttle plate to increase the idle on a cold engine. When the computer senses the engine warming up, it closes off that extra air. (Am I correct so far...?).
I understand the IAC is a stepping motor. If the pintle and seat are clean, the EGR clean, and no vacuum leaks, what would cause the idle to run high (2500+) for about 3-5 minutes before settling down to a normal idle?
I suppose the theory would apply to most fuel injected/computer engines, but this particular motor is a 1990 Suzuki/Geo 1600cc that just had a valve job.
Any help, thoughts, advice, etc. would be appreciated.
