I stand corrected: Carfixer007 is correct.......

In this system, there is no relay to activate a compressor clutch..... the A/C compressor is constantly belt driven........

I spoke too soon....I read up on this system, and it is as described by Carfixer007.....

Have you removed the belt and rotated the pulley by hand to feel for roughness in the bearing?

Have you tried a mechanic'* stethescope on the compressor to confirm the noise?

Is there a difference in noise when the compressor solenoid is activated, and when it is not?

My 2011 Buick LaCrosse has a noisy A/c compressor, the noise sounds like a bearing noise, the noise does follow acceleration or (changes with acceleration) the compressor does run a the time and unplugging the power does not shut it off. Cooling still works. I can’t find any info or parts for this compressor on the web. Any help would be deeply appreciated. Thank you

I want to thank you all for responding and I apologize for not replying back (life got busy and it’* a second car ) if I unplug the compressor the clutch stays engaged. I will pull the belt this weekend and hand spin. I have run the motor with the belt off and the noise is not internal of the motor. Any suggestions on where to find a complete description of this compressor. Thanks for your time

I have used the stethoscope to isolate the noise (after I replaced the idler pulley lol)

No change in noise when solenoid is activated

What did the stethoscope tell you? Front of compressor? rear? Bearing?

The rear was loud. It’* more of a whining sound. A/c does still work.