I have replaced just about every sensor on this: ECTS, Air TS, IAC, TPS, MAP, inlet O2 sensor. New plugs and wires. Checked for vacuum leaks. If I start it cold and just let it idle, it will quickly drop to 1200 rpm in less than a minute, the hunt down lower in RPM to about 1000. It is missing a little at that lower speed. After that, it will in a few minutes rise back up to 1200, then 1300, then 1400 rpm. If I start driving then the minimum idle during a shift will pop up to as much as 2000 rpm, as if it is cold. As soon as I stop at a light the rpm will drop to 1300-1400 again. It doesn't seem to be missing at the higher idle rpm and still gets great mileage. I got 36 mpg on my last 4 hour drive.
Besides what could be wrong, does the outlet O2 sensor have anything to do with idle rpm on this engine, or is it only tied to the cat failure sensor? I haven't replaced it yet. :
have the same problem?
Thursday, April 19th, 2007 AT 4:46 PM