Here's one for you 5.0 Stang guys/gals- Fast Idle after new IAC- no CEL

Ok,
1995 GT 5.0, 163k miles, 5 speed, my dad's. A couple of weeks ago he called me and said he heard a "pop" and now she sounds like a foghorn and idles at
2k. Did some research, indicated a bad IAC. We replaced it and the foghorn noise has gone away, but she still idles at 1500. He searched some Mustang forums and found the usual suspects; disconnect the battery, etc. We did that, no CEL.
Before we start messing with the idle adjustment screw, any ideas?
Steve in AZ
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Unplug the IAC.... if the idle drops way low, it could be the IAC (they only go on one direction). If the idle stays high, suspect a vacuum leak.

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Be aware that is NOT the idle adjustment screw. I think what you are talking about only regulates how much air you get, this screw in no way will change your idle speed.
Guess how I know?
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Ok, how do you know????
Steve

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Jim,
Many thanks, We found that the Autozone IAC we got is bad, It doesn't fluctuate at all and my dad's on a fixed income. He's going to return it and hit the local pic-a-part for another. He's going to get her detailed and sell her. I hate to see it go, it's a great car, new top end byt it's his car....I'll file this under "good to know".
Thanks again and God bless!
Steve

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