my engine can't seem to maintain a constant idle, constantly revving up and down.
I had this problem with my Zetec, it turned out to be bad fuel injectors for me. It seemed to be heat related for me too, if it was cool out it wouldn't do it as much, but if it was warm it would do it all the time. I can't say if the injectors are your problem, but it's a posabillity.
It was funny at drive ups, because the people at the other end of the mic. thought I was reving the engine
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