Q: Humming sound when AC on

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Hi, I hear humming sound when turning on AC, it's louder when accelerating, also acceleration seems sluggish when AC on. If no AC there is no sound and car seems normal. Note: AC is blowing cold air and no issues.
My car has an automatic transmission.

If the noise gets louder when you accelerate and goes away with the A/C off then the problem is with the internal bearings within the A/C compressor itself. You should have the A/C compressor checked and replaced if noise is verified to be internal. If you’d like to get this fixed, consider YourMechanic, as one of our mobile experts can come to you and diagnose the sound you’re hearing for an accurate repair.

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