New noise with the air conditioning

I have a 2003 Saturn Ion, 5-speed, manual transmission, with about 95,000 miles. This week, whenever I turn on the air conditioning (high, low, or in-between) a whirring or revving or rumbling sound comes from under the hood, close to the car, center or passenger side. It sounds I’m driving a huge truck. The sound doesn’t change with RPMs or MPHs, idling/neutral or in any gear.

The sound will begin shortly after I turn on the a/c and sometimes stop by itself. When it stops, especially if I’m not moving, the car gets so quiet (and there’s just maybe a hint of hesitation) that it almost seems like the car has stalled. When I turn off the the air conditioning, the noise stops just after. But the whole time the a/c is on, it’s working just fine, nice and cool.

I’ve been all over the g**gle and this website and I can’t seem to find anything about this problem. Compressor? Condenser? I can’t seem to find anything out about this. I welcome any suggestions or direction. I was hoping to find out a little bit about the problem (and potential repairs/costs) before I head to the mechanic.

Thanks in advance for any help you can offer!

Have someone check if there’s a problem with the radiator cooling fan motor.

When the air conditioning is turned on this automatically turns on the radiator cooling fan. This is the only thing that’s related to the air conditioning system that can make noise but not be effected by variable vehicle operating conditions.

Tester

Thank you!

In addition to the radiator cooling fan, have a mechanic check the compressor clutch.

Thank you!