Need help with diagnosing a high idle
An IAC count at 0 should mean the IAC is completely closing off the IAC passage way in the TB. That is if the PCM has the circuits to control it and if it is wired for it. It could mean that it is all correct and the PCM is commanding 0 in an attempt to lower the idle speed. Use the bidirectional controls in the scanner to command a certain IAC count and see if the IAC position follow what you command. If it does, they you are getting air in the engine from a source other than the TB/IAC. The only way an engine can increase rpms is to give it air. Also have you verified that the TB is completely closing?
Looking at that I'd say you need to find the air leak.
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Guys, I taped up and blocked the IAC port on the throttle body (removing the IAC valve) and the car started up and purred like a kitten at around 750 - 800 rpm
Put the valve back in and the RPM jumped to 1500 - 1800
It's GOT to be a bad IAC, programming or something in the harness
I'm going to double check my wiring and try and figure out how to test the wiring to make sure I am getting the appropriate signals
Throttle plates are closed BTW when it is idling high
Put the valve back in and the RPM jumped to 1500 - 1800
It's GOT to be a bad IAC, programming or something in the harness
I'm going to double check my wiring and try and figure out how to test the wiring to make sure I am getting the appropriate signals
Throttle plates are closed BTW when it is idling high
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Got it fixed, I bought that new IAC and was still having issues so I decided to swap out the stock TB for the aftermarket polished one I bought a few years ago.
Started right up, idling a hair below 1000 rpm and staying there. I swapped this aftermarket for a OEM one a while back when I was troubleshooting but I guess the IAC was bad then, and the used original TB I bought have had issues as well.
All is good now
Started right up, idling a hair below 1000 rpm and staying there. I swapped this aftermarket for a OEM one a while back when I was troubleshooting but I guess the IAC was bad then, and the used original TB I bought have had issues as well.
All is good now
