I replaced the dryer and compressor two years ago. Now it's making a weird liquid surging sound. It's not the belt. I think I put enough PAG oil in it.

The noise happens every ten minutes or so of driving. Lasts for a few seconds then quiets down. It's still cold and I don't think there's a leak.

Should I vacuum it down and refill?

 

What exactly is making the noise? Are you certain that it's coming from the compressor?

Does the AC work properly?

 

I heard the noise last summer but ignored it. I'm not sure where the noise is coming from. I've only heard it while driving.

It sounds like liquid swooshing through the lines. From the driver seat, the noise seems to be coming from the evaporator area. The A/C seems to work fine.

 

First thing is to pinpoint it to a specific system.

How's the coolant level? Good heat? Could just be coolant flowing through the heater core.