What could this be... it seems to happen mainly when it's cold. It doesn not stall however it revs up and down up and down. Any common issues this could be???
Please help it's for a friend and I know nothing about the 12V.
He needs to clean the ISV (idle stabilzer valve) with somw Gumout Throttle Body Cleaner. Take the plastic cover off the top of the motor (the one closer to the fire wall) and there is a metal looking valve with an electrical connection on it and 2 vacum liines. Remove the 2 or 3 torx head bolts, clean it out, let some cleaner soak in it for a few mintues, and then blow it dry with compressed air. Re-install....clear codes if you have acess to a scan tool and you should be fine in about 5 mintues of driving....
this can also happen when you have a broke PCV valve, mine is broke but i can pop the piece that runs from the mani to the intake tube back into place and it will be better, but it will jump from like 1500 back down maybe stall jump back up, its crazy when there is vacuum problems http://****************.com/smile/emthup.gif
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