4 Attachment(s)
Finally found the problem!!!
Problem Solved!!! -Aveo 2008 BIG Automatic-
First of all I'm Happy that you solved the issue with some carb. cleaner through the air valve. I had the same issue but carb. cleaner didn't do the job. Also I tried removing and cleaning the whole throttle body (completely) but that didn't work either. turning open the Idle Stop Screw helped the issue temporarily.
My high rev symptoms were:
1. High revs in neutral (1500 - 2100).
2. Higher rev. when changing gears than usual (about 1000 to 1500 higher than usual).
3. Engine check light went on occasionally (Fault P0122 - Throttle pedal position sensor / Switch "A" Circuit low input).
4. High revs were absolutely random; engine could work fine for a week and then go "crazy" for a few days.
And finally the solution... while the car was high reving (1500 to 2000 in neutral instead of 670rpm) I pulled out the TPS (Throttle Position Sensor) plug out and found that it solved the problem; the revs dropped down to normal ~670rpm while the engines computer used default signal values (the engine check light went on as well - checked it with an app and a bluetooth obdII device and it said P0122).
What I did next was buy a new OEM TPS sensor; replaced the old one and it solved the problem (and the engine check light went off as well).
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