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Q: Squealing noise when you start the car

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If the air conditioning is on it makes a loud squealing noise. We've changed belts wigh no kmprovement

My car has 2282452 miles.
My car has an automatic transmission.

A: Hi there. Depending on the engine and type ...

Hi there. Depending on the engine and type of car you have, it may change the diagnostics. I suggest checking the a/c belt tensioner for proper tension on the a/c belt. If the tension on the belt is okay and the tensioner is okay, then the a/c compressor is causing the belt to squeal due to a locked up compressor. If the noise goes away when a/c is off and comes back with a/c on, then the compressor will need to be checked to see if it is locking up. This is due to having a bad compressor or a blockage in the system causing the high pressure side to be blocked. The condenser or expansion valve and drier may be blocked. I recommend having a technician, like one from YourMechanic, inspect the air conditioning system and replace any failing parts.

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