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Q: Compressor it AC Belt?

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When I turn my car on, whether the AC is running or not, under the hood has a louder than usual running noise. I was told it could be the compressor or AC belt. Is this what it could be? Also, if my AC is on high I notice non-odorous smoke coming from the vents. Thanks!

My car has 119097 miles.
My car has an automatic transmission.

A: Hi there. If the belt is failing or if the ...

Hi there. If the belt is failing or if the AC pulley bearing is failing, then this noise can occur. I usually remove the belt and check each of the pulleys to see if any of them are rough indicating a bearing failure. I would then replace any questionable parts. If they are fine, then the noise may be coming from the engine. As for the smoke from the AC, if the system is working good then most of the time this is condensation that is coming out. It usually is the result of a clogged evaporator case drain which allows moisture to build up and then it ends up coming out of the vents like this. If you need to have the engine noise and the AC vapor issue looked at, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose the noise and smoke problems in order to have this correctly addressed.

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