8 yr old mazda 626 75k miles around town miles -
when air cond is off under hood noise from compressor area is louder, turn a/c on and noise becomes less- noise sounds mechanical its not belt squeal.
why quieter when a/c is turned ON?
sorry, you'll have to find some ways/means to upload the sound (yotoob?).
Without that,we are just playing guessing game (and so many things under the hood can be at fault).
true, my friend had the power steering pump replaced and that helped a lot but the noise now still gets quieter when you turn on the a/c. based on that I told him its probably not the compressor, since it would howl when on. the mechanic told him he needed a new compressor. maybe its the clutch and they cant buy the clutch seperate?