Rough Idle with AC on
2002 Focus, Auto Tranny
I had the alternator replaced last week. Now I get a very rough idle (stumble) with the AC on when stopping at traffic lights. Tach seems to bounce between 700 and 100 until I turn off the AC. Idle returns to normal once AC is off.
If I turn on the AC while stopped this does not happen. Only happens when slowing down.
Is there a sensor or electrical connection that controls the idle that may have been affected by the partial car disassembly involved with an alternator replacement?