SL/R129: Rough Idle when AC is on
07-03-2007, 10:18 AM
#1
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Rough Idle when AC is on
Hello...this is a fairly new problem...rough idle when ac compressor runs - idle is fine if I turn off the air. Car has 100,000 miles (92 500sl), sits in garage a LOT - right now about 50% of the gas in the tank is 6 months old, but I don't think that is the main cause...any and all ideas are welcome...thank you!
07-03-2007, 02:54 PM
#2
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If the idle is rough because the engine RPMs have fallen, then I would suspect the idle speed control. On your car this is an air valve in the intake which regulates the amount of air that bypasses the throttle. It is controlled by the fuel injection control unit.
I would read diagnostic codes for the fuel injection. The procedure has been posted and referenced many times. If you need help for codes, you can use the search or send me an email.
I would read diagnostic codes for the fuel injection. The procedure has been posted and referenced many times. If you need help for codes, you can use the search or send me an email.
