AC Question

[Heliogordy]

I have a question I'm hoping you tech guru's might have some insight into.

AC compressor would not kick on my 2010 LT when I bought it. Took it to local mechanic (who has been very reliable in the past)...low on coolant...quick evac and recharge and it was painfully cold....problem was it also whined like a damn siren at speed. Took it back, and he admitted he didn't test drive it after starting it up and checking things out and didn't notice the whine.

Two options...new compressor alone or new compressor, condenser, evaporator, etc. I told him I trusted his judgement. Next day, he calls and says, "we flushed everything and everything is SUPER clean...think you just need a new compressor, so that's what he installed.

After driving it for a few hours, a less robust but still prominent whine returned along with a sound I could best describe as a "gurgling" noise when at idle. Both sounds come and go...more prevalent the longer you drive and stop the second you turn the AC off. Still VERY cold...Taking it back in tomorrow......anyone have any insights into what it could be? I've had other mechanics suggest a system overfilled with oil, air or water in the system or new compressor that was crap right off the shelf. Any suggestions greatly appreciated.

BTW...man, I freakin' LOVE this car!!!

Thanks again for allowing me to post on your forums.

[SS_CTS-V]

Small chance the gurgling is a little too much oil in the AC system, but it's not the end of the world. Shouldn't be harmful, just a little annoying. Also likely it's a bubble in the radiator/coolant system. My wife's Mercedes gurgles like a small creek sometimes.

The whine is either a bad compressor (not unheard of) or actually something else on the car, that coincidently happened around the same time. Take a close listen to the alternator.

Sounds like your mechanic is competent and being straight with you.

[152LTRockin]

Could be something else making noise other than the compressor. I'm a AC tech and I noticed in my Camaro the compressor isn't exactly quiet but it works good and is properly charged. Unfortunately these Camaros use something called a Expansion valve, it can really be a PITA to diagnose If its failing or just not working properly. Why GM decided to go BACKWARDS in technology is a mystery.

[Heliogordy]

Gurgle and whine both occur while AC is running....the minute I turn the AC off, BOTH sounds immediately quit. Sound is really annoyingly loud unless you drown it out with the radio...shame is that it's freaking COLD...coldest AC I've ever had in a vehicle.

[152LTRockin]

Maybe a little overcharged some liquid getting back to the compressor will make it noisy.

[Heliogordy]

Originally Posted by 152LTRockin

Maybe a little overcharged some liquid getting back to the compressor will make it noisy.

A former student of mine who now works as an ASE certified mechanic at our school corp bus garage suggested that, too. He offered to check it out, but it's still under warranty from the repair shop.