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Q: When I turn the AC on, it makes like a rattling noise under the hood. As I keep the AC on, the sound gets louder.

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Rattling noise when I turn AC on and it increases if I continue to leave the AIR on

My car has 41000 miles.
My car has an automatic transmission.

A: Your car’s air conditioning system is drive...

Your car’s air conditioning system is driven by an air conditioning compressor that has a small clutch on compressor pulley. When this becomes worn out or not properly lubricated enough, this can cause it to fail which can make a very loud rattling noise as you describe. To avoid any unnecessary repairs, I would suggest having an expert from YourMechanic come to your home to diagnose your AC system and help you fix it accordingly.

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