Not thirdgen related but still f-body though.

I bought a 1994 Trans Am late last year. The car's airconditioning worked great when I bought it, but after a 1000 mile drive home it wouldn't work at all. I didn't need to use the a/c at all during the drive so I don't know whether the gas slowly leaked out or the compressor went kaput all of a sudden.

I got a recharging kit from Walmart complete with a pressure gauge and hooked it up the car. I'm kinda unsure as to whether I hooked it up to the low pressure side port though. It would fit on only one port but when I tried charging the system, the gauge went into the red and the compressor didn't even start cycling. I'm thinking I hooked it up to the high pressure side, that's why the compressor didn't suck anything in at all. But then again, the hose wouldn't connect to the other port. Is the low pressure side port the one by the passenger side exhaust manifold or the one by the radiator cap on these cars? I'm pretty sure it was the low pressure port I hooked it up to. It had a blue cap on it.

Another observation I made was that if I turned the valve on the can open the pressure would shoot up into the red but come back down to zero eventually if I closed it, even with the motor running and a/c on max. That certainly doesn't seem normal.

Any ideas would be greatly appreciated. It's getting really hot and humid here.