c300 2010 making a whining noise simular to a power steering pump whine...what can it be?
It could be any of the pulleys that the belt drives. ac, idler, tensioner, water pump, alternator etc.
I recently had the exact problem - I thought it was the power steering pump. Took it to Mercedes. Turned out it was a high pressure line or fitting. Sorry I don't remember which one it was. I think it was one of the air pumps.
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