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Q: When I turn the ac on it makes a very loud squeal that stops after a few minutes. 2007 Jeep Commander

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Yesterday my alternator belt was removed because of one of the pulleys also making noise. After that the same belt was put back on. Today when I turned my ac on for the first time all day it made a loud squeal after I turned the ac off the squeal stopped. It happened on both the cold and heat settings. I have no idea whats going on but its scaring the crap out of me. Im praying its not my ac compressor. Could you please give me an answer as to what on earth happened? It was literally over night.

My car has 147000 miles.
My car has an automatic transmission.

A: Hi there - It’s possible that the tensioner...

Hi there - It’s possible that the tensioner/idler pulley for the serpentine belt(https://www.yourmechanic.com/services/loud-squealing-or-rattling-is-coming-from-engine-inspection) by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

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