Ford Repair Questions? Ask a Mechanic for Answers ASAP
The first step I would take is to spray some water on the belt and see if the noise stops. If it does, then replace the belt. If not, then all you can really do is remove the belt and spin the pulleys by hand. Usually if one is failing you can hear it vibrating or feel roughness in it when you spin it. If everything is good to go, and feels fine, then it's probably the tensioner. This is about the only way to trouble shoot this type of issue and yes, it's a pain to do, but never the less how we do it.
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