I was reinstalling my idle conrol valve back into my ported TB and noticed that the pintle did not touched the seat. What I mean is that it is now open somewhat and you can blow air through it. Do you know if the ECM will close it at startup? Will it self adjust as necesary and work OK? Or does it need to be close to begin with? The IAC is in the same exact position as when I took it off and the porting did not touch that area. Thanks.

The IAC valve is set by the ECM while driving over 40mph for a minute or so. Usually when you install one idle is high. Drive it around over 40 and ECM resets it and idle returns to normal.

I just asked a similar question on mine because I replaced the IAC and screwed it in before installing. I have driven over 40 and the idle is still high so I'm thinking that the ECM only moves the IAC a certain distance causing a high idle if it's not adjusted properly, not sure yet though

The IAC has been my project this week...even going so far as to set one on the bench and make it move. This is my take on it.

The IAC is calibrated by the ecm when you drive above 40 (or is it 45?) The calibration is merely closing the valve- seating the pintle in the orifice.

At idle, the pintle is retracted awayfrom the orifice. I came to this conclusion by examining an old (and bad) IAC and a new IAC. After idling a bit, I'd remove the new IAC and its pintle would be withdrawn. everytime. the old one would be extended- even after Id manually retract it and reinstall it.

So, Ive come to the conclusion that a valid check of your IAC's operation is if the pintle is retracted when you remove it.

[This message has been edited by Linx (edited 06-05-2000).]

Good input Linx. Today is the great day I'll fire up my new 3.4. Maybe drive it if I can reinstall the struts. Hope to get to the 40-45 MPH and get the IAC readjusted. Thanks all for your inputs.