I wonder if you guys can suggest reasons for AC compressor very noisy upon engaging in my wife's1993 Volvo 240. Car was purchased this year, from friend of mine. Original compressor Seiko SS-121DS5 compressor was very noisy and almost seizing when engaged, so I replaced it with brand new remanufactured model, replaced the dryer as well. System re-chared with PAG-100 oil and R-134a refrigerant according to manuals. Checked for leaks. The AC is working, but new compressor, while less noisy, still occasionally emits the high pitch noise and at same time seems to hold back the engine on power. If anyocan can offer some suggestions, I would be very much obliged.

Thanks,
Alex...