I'm curious if others have had similar experiences. My '94 Volvo 940 n/a, 211k miles developed what I thought was an intermittent "miss" while driving. It felt like a full revolution was dropped and the whole car jerked. When the A/C stopped working, the problem went away. I've had intermittent trouble with the A/C, mostly a sudden loss in cold air in the dash vents, then sudden return of cold air. I discovered that the clutch was creating sparks at high RPM (3500+) and seemed to be slipping a little bit. Then I discovered that the clutch plate is bent -- one area along the edge was bent out, away from the compressor. Don't know if it's important, but I've gone through 2 pressostat switches in 3 years. The "missing" feeling has been around for nearly 18 months. It went away for awhile, but returned when I had the car on a trip. Up until the A/C stopped working, at its worst the "missing" feeling occurred about every 5 miles or 5 minutes.

I have the compressor and clutch assembly out to replace it. Obviously at least the clutch is bad. The odd thing is that everything turns freely - clutch, compressor shaft, etc., although the clutch bearing sounds a little rough. I'm wondering if it was drawing too much electrical power initially that put a strain on the engine. I'd like to hear from others if anyone has had similar experiences or has any thoughts.