I had a high pitched squeak/squeal that would come and go on my C230. A couple of nights ago I came home and noticed it was pretty loud so I thought I would track it down. I put my mechanics stethescope on everything I could think of and couldn't find any bad bearings. In fact the loudest one was the alternator which was the only place I was pretty sure it was NOT coming from. (Didn't really sound bad, it was just the loudest) I moved all around the car trying to localize the origin of the sound. It just seemed to be coming from everywhere the belt was. I had inspected the belt just a few days before and noted that the tension was good but the surface looked a little old and had tiny cracks in it from age, even though it is only about 2 years old I think. Anyway, I considered that it could be just the belt itself. As an experiment I dipped a toothbrush in water and touched it CAREFULLY to where the belt goes around the tensioner, where the V part is on the outside. ** Do not do this at home !!** Might not be safe on other cars!!! Anyway, as soon as I touched the belt, the sound would stop for about 2 seconds until the water dried off. I imaging you could do the same test with a spray bottle and that would be a lot safer! I have ordered a new belt and I believe that will solve the problem.

Mike

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra