After I had the fan clutch replaced on my 94 S500, I started hearing a low pitched noise (whine) when the engine hits the 1500rpm mark. It seems to be coming from the engine compartment. The repair shop that did the work told me it had nothing to do with the fan clutch and that it was coming from the tranny tunnel. I've taken my car to this shop a couple of times. they'll fix one problem but then another one would come up after I get the car back from them

Needless to say, that was the last time I went to them. Anyway, any ideas regarding the low pitch noise? Thank you.