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A/C Help Melting in Miami--Pont G6 08

Hello, here is my issue: several months ago, my a/c started to only work about 50% the of the time. The air was flowing, but not cold. I noticed that when it was working, I heard a fast clicking/chirping sometimes. Also, the check engine was on, usually just when the air was not being cooled. I finally took it into the dealership and they said it was the thermostat, fixed it under powertrain warranty, and I was happy…until a few days later when I noticed it was only blowing about 65 degrees, if that. Did they diagnose it wrong, or install the thermostat wrong? Should I take it back there, or find someone else?

I would say either the AC compressor or belt that drives the compressor. It could be low on refrigerant, which would also cause it not to work. The thermostat would not cause the ac not to work. The engine would overheat if it was bad.

You shouldn’t expect it to blow air colder than ambient temperature minus 20 degrees. Has it been in the mid-80s much?

Did the dealer test the system pressure? What was the pressure on the low side and high side?

knfenimore: I agree, now that I’ve done some reading about it. Thanks.

jtsanders: I disagree about ambient minus 20 deg. I’ve read a number of sources that their delta T can be up to 50 deg F when it’s 90 deg F outside. Also depends on air saturation. Regardless, it was about 80 deg ambient blowing about 70 deg. I don’t know about the pressure. The dealer didn’t say what the numbers were.

Here’s a troubleshooting guide to help familiarize you with AC operation. When you talk to a mechanic, you will better understand what they found. If they don’t tell you much, it will help you ask questions.