Could it be water pump or timing belt problem?
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2000 Pontiac Montana Question: Tinny front of engine noise
Answer #1Bret Bodas from RepairPal Test Shop, April 15, 2009, 09:32Master
yes and yes. Have it checked out very soon, if something fails, it can do some expensive damage. Consider the sound a very important warning!
Replyjohn48, April 15, 2009, 11:23Rookie
Bret, turned out to be air-conditioner pullies not used in Michigan for a while. They told him to just put the air on at the lowest level and let them adjust. What a garage they are!!! Regardless, I told my brother to replace the water pump and timing belt anyway.
They didn't charge him anything for their advice.
Answer #2Visitor, August 29, 2010, 18:41
another possibility is the belt tensioner. if it makes noise too long, then it just flys apart.