I've got an '00 GT, 3.8L non-supercharged, with about 75K on it. I have the problem that when the weather gets heated up, and I believe more importantly, gets really muggy, the A/C likes to cut out while I'm driving. It started last year on July 4th actually, and I again noticed the problem this year around the end of June. I started watching more closely and noticed it occurs when the RPM's reach 2-2.5K, either during acceleration or just cruising the highway. The air out the vents starts getting warm since the compressor cuts out and all it has is the residual cold in the coils. If I let the rpms fall back to like 1.5K, then the air gets nice and frosty again.

The thing too is that it doesn't always cut out. Sometimes it will stay running, sometimes not. Cruising at around 2K, sometimes it works just fine, other times the compressor keeps cycling, but far more frequently than it should for the MAX setting. The high pressure sensor was replaced last year, but no go. I thought perhaps one of the cooling fans was bad since it seems to work better at higher speeds where more air is flowing through the condensor. But they fans look like they are running fine, but that's no guarantee they are pulling the volume they should. I can't afford to go replacing parts willy-nilly in the hope I get the right one. Any thoughts on where to find this gremlin? Thanks!

ive seen a similar problem with the mother's car. just recharged the system with a can of refrigerant and it fixed the problem. most auto stores should have a can and a kit with directions, it's not too hard.

Always becareful when working with pressurized systems.

I know that the A/C is tied into the tps so when it's WOT the compressor will kick off. I wonder if maybe there is something wrong along those lines.

Sounds like a charge problem or your ac isnt getting enough power. Check to make sure the voltage/amps are constant over 2-3k rpms

with the recharge kit, you are working on the low-pressure end of the AC system.
just be SURE of the connection you are using, and that you're on the low pressure end.... the high pressure is extremely dangerous, but the whole recharge procedure is quite easy.

I thought it was low coolant last year, but it was recharged twice to full capacity and they did leak tests and didn't find any leaks. One thought brought up at the parts store was that it could be a malfunctioning cycler switch. I guess it's purpose is to keep the compressor from freezing the system up by cycling it off and on. This may be a possibility.

Hello, I am new here and trying to diagnose an A/C issue as well. My wifes GP has been acting up. It seems to be something with the AC as well. All works fine as long as the fans speen is on 5. If you take it to 1-4 the AC shuts off and the head lights turn off. SOmeone tole me it is most likely the alternator since it has the internal voltage regulator(not sure about that). Has anyone ahd this issue? Anyone have any ideas.

Thanks in advance.
Jim

Common problem there. You need to replace the blower resistor. It's located on the firewall iirc in front of the center console. PITA to remove easy to install.

Good deal. I guess it is good that it is common enough for people to know about. Do you know if this is a AutoZone type part or a dealer part?

Also, is it something a shad tree car buff can change out?

Thanks

It sure is. As for an autozone type part I doubt they'll have one on hand but I bet they can order one for you.

Well, after taking the seat out and 3 hours of strugling I got it switched out. Well, that was not it. What else?

I found a few others on here talking about this issue. I wonder if it is the ignition(sp) switch?

BTW, I got it from the dealer. They said, it was not common, but it was also, not-uncommon. What ever that means.