The engine idles excessively high after sitting overnight in cold weather. Example: The engine starts and will idle normal; After letting the engine warm up for a minute or two, I'll drive the car a short distance, then put it in park; at that point the idle speed surges extremely high, as if I have the gas pedal pressed 2/3 to the floor; I'll put it back in drive, and the car will buck so hard that sometimes the tires will chirp, then the idle speed will drop significantly, yet is still very high; If I put it back in park, the idle speed surges again. The problem seems to diminish the longer the engine runs, (i.e, a 30 minute trip) but the engine can be fully warmed up in cold weather and it will still occur. I've already replaced the spark plugs, EGR valve, and thermostat. Any help would be greatly appreciated.
Dec 19, 2009 at 2:33 PM