i just changed my 2005 Sienna AC compressor 2 months ago. Now I have noticed a loud sound when ever I turn my AC on. It gets louder when I slow down or on idle .
The sound is not shrieking but it's like a louder engine-like sound or motor-like, like a loud hum. No vibration noted. I hear when AC is on, especially when I am slowing down or at idle ( maybe because I hear it better then?). But noise is gone when AC off. One mechanic said, I might have a defective compressor. Any ideas?
Sounds like the compressor clutch is slipping. It can be adjusted by the right person that knows what they are doing but since it is not that old where you had it done should take care of it.
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