Take 1 belt off at a time, and run the engine. When the noise is gone, it would be one of the components of which the belt drives on. I've had a customer that has come to me w/the same compliant, and wanted the alternator replaced. The real issue was the pulley that you can adjust the tension of the belt. When you have the belts off, turn each pulley by hand. If they feel loose or feel rough, replace that one first. But of course replace the worst ones first.
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Monday, December 7th, 2009 AT 8:39 PM