Okay, that tells me one of three things. Either the belt is loose due to a bad tensionier, the belt needs replaced, or one of the belt driven accessories is locking up and causing the noise. Check belt condition and tension first. IF they are good, remove the belt and check each belt driven accessories to see if any are hard to turn or making noise.
Let me know what you find.
Nov 30, 2011 at 1:07 AM