We've had my wife's car for about 3 1/2 years now, and keep it well maintained, so it was a total surprise when one day, the A/C stopped pumping out cold air. I got my tools, my Chiltons, and a coolant refill tester and kit (I think it was R134A). I did all that I could think of, all the fuses were fine, the refrigerant was only slightly low, the idler pulley on the pump was kicking off and on fine, and everything else on the climate control panel was working just fine. I was holing someone out there might have some suggestions or advice on how to diagnose and fix this as cheap as possible. Thanks for your time and the read.

Does the metal piping to the evaporator on the firewall get cold from the AC compressor working to pressurize the freon?

If so, then on the inside, is there air coming out somewhere? defroster vents? floor vents? It has to come out somewhere if the blower motor is running.

Is the blower motor running? Are you able to change the speeds on it?

Are you able to change the temperature of the air coming out _somewhere_ by varying the temperature settings on the dashboard? Hot, hotter, hottest?

Thanks for the reply. No, all of the piping is very warm. All the interior and climate controls are working fine, all the settings, modes, and speeds work just fine, except the A/C, which still blows as it should, but is hot instead.

So the middle of the compressor pulley would lock on and start spinning with the belt? It is not supposed to kick on and off. Your car has a variable compressor and it stays locked on and adjusts the amount of freon pumped rather than turning off.

How did you check the freon level? It should be by connecting a gauge to the low pressure side with the engine running and the AC on high.

The pulley or whatever it may be, the exterior part has always started spinning when the A/C is turned on, and stops when it is turned off, but the interior pulley keeps going. That is exactly how we tested the freon levels, and it showed only a little low, so we topped int off.

I have the same issue and about the same exact story. I have probably wasted so.much money and freon.its not even funny. Everything is up to pressure. My compressor kicks on and off. When.I say that I mean it stays on for a while then goes off. I was getting cold air then boom got warm air. Its 90 degrees lately in pa and I want this thong foxed badly. So I charged it up some more. Now the compressor wont even kick on!!! So frustrated at this. I wasted two days trying to mess with this..GET THIS!!! Now the button for Ac doesn't even respond on the digital screen now. So when i put the climate down to 60 degrees on both sides and hit the Ac button and I have fan.on.max and have the front five vents on and I hit the Ac button and still says "Ac off" what the heck?? Hit it multiple times. Nothing. Hit it more. Change vents to the dash and the "Ac off" just blinks. I found out why it blinks. Pontiac designed it to not Ac the windshield due to fogging it up which thats fine but when I just put Ac lines on and getting 45 pounds of pressure that dang low pressure sensor should tell the ecm there's pressure in there. Which thats located by the little canister. I bought a pump at the yard for back up when.I got the lines. But I know that thing works. I just dont understand why the "ac button" wont.put the word "Ac" on the digital screen? Thank you for taking.your time.to read this. I really.need help badly. Thank.you thank.you

I have the same issue did you ever get this resolved?

My AC quit working and i found the Grounding block bolted to the top of the trans had been pulled apart (had transmission replaced). took apart and straightened pins and put back together... Walla it kicked the AC on again.

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Shane "RedZMonte"
2004 Z16 Z06: Virgin
2000 SSEi: Kenwood DDX512, 3.25" MPS, ZZP DP, PLog, Puck Mount, NGK TR7's, DHP Tuned
1995 Monte Z34: T04e "60" turbo, 42.5# injectors, Borla Catback, OBDII swap, DHP Tuned, Much more...

More than 1 owner has reported that the fusebox connection had loosened for fuse #34 (IGN 3 Rear) fuse in the under seat fuse box.
Tightening the connector fixed the intermittent AC warm/cold issue.

ok, forgive me , but is the compressor engaging or not - easy to find out if you got a cheap gauge - with ac off, you should get over 75 psi - once the ac is on, you should see the pressure drop to 25 -60. does it do that or does the pressure stay linear all the time?

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poverty forces one to do unorthodox things

2000 SSEi
past rides:
1996 SSEi
1992 GTP
1987 Grand Am

If you over pressurized the system, you will blow hot air. IF you are low on refrigerant, you will blow hot air. IF you don't have adequate flow across the condenser, you will get hot air. You want to put a real set of gauges on the system if you haven't and look at both the low and high side readings. Trust me, after picking up a set, they are invaluable, and as long as you own cars, you will have a need to have them. IMHO, they are as important in your tool box as a 10mm socket is.

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A temporary fix does not exist. It becomes a solution until it needs to be fixed again.

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