I have an 02 Expedition. The RPM gauge is running high. We replaced the idile air control valve. Not sure where to go next. It's still running high.
I would check for vacuum leak. Possibly pcv valve stuck open. Also did you by the iac from a reputable store? I bought two on line that were cheaper than the ones at the auto parts store. They were new and just like the factory one BUT they were bad right out of the box. Ended up buying the high price oem part and all is good now. All because they say its as good as oem does not make it so.
On the money dandy.
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