IAC question

[dgreen1069]

What would cause my IAC numbers to change from time to time? I set my IAC about a week ago to around 20-25. Today I noticed it had gone up to around 60. I again reset the IAC to 20-25. The car sat for a while, then I took it out again and noticed the IAC was between 50-60. Is this normal or do I have a problem?

The other thing I have noticed is that you are supposed to set the IAC then the TPS. I have found that the IAC #'s change when the TPS is changed. Is this normal? I have been using the instructions provided on GNTTYPE.ORG.

 

[Tampa T-Type]

Changes

The TPS has a direct effect on the setting. Check for vacuum leaks I had the same issue.

 

[dgreen1069]

Would a vac. leak affect the IAC #'s? Other than the wastegate sensor, where are the most common vacuum leak areas?

 

[bruce]

What would cause my IAC numbers to change from time to time? I set my IAC about a week ago to around 20-25. Today I noticed it had gone up to around 60. I again reset the IAC to 20-25. The car sat for a while, then I took it out again and noticed the IAC was between 50-60. Is this normal or do I have a problem?

The other thing I have noticed is that you are supposed to set the IAC then the TPS. I have found that the IAC #'s change when the TPS is changed. Is this normal? I have been using the instructions provided on GNTTYPE.ORG.

What are your BL's doing?. Too lean or too rich, and the idle may hunt a little and the IAC will try to compensate. If the Bls have changed, you might be chasing a vacuum leak.

Might try cleaning out the IAC, and it's passage ways. When they get enough carbon floating around in there that also can cause problems.