Need a little a/c help-98 GT

[Mjavant1985]

Hi all,
Basically my a/c has quit working and blows nothing but hot air, and wanted to see if anyone knew what was wrong and i could fix it before taking it to an a/c shop.
I bought one of those cheap freon cans from wal-mart first as a cheap way to see what was wrong. I cut a/c on max and comprssor wasnt engaging.
Attach the guage and freon can to low port pumped a little in and compressor engaged for about 10 seconds and cut off, and would stay off for about 5 seconds and cycle that again.
The guage was reading low when i first hooked it up and when the compressor would cycle on and off after adding about 1/4 can it would read full to nearly overcharged, and when the compressor cycled it would go back to low again.

So i cut the car off and unhooked the can, and it seemed everything i put in the lines come back out the low port side.
Any ideas?

 

[sethahoward]

Add more freon. It needs to be in the full mark while the compressor is running. Don't worry about what it says when the compressor isn't running.

 

[blacksheep-1]

You really need a set of gauges to do diagnostics, but it looks like the unit needs more freon to me. You also have to be quick on disconnecting the lines and probably should use safety glasses. I don't recall if your unit uses the new quick connects or not..it's been awhile. to ID the low side line, it will be up stream from the compressor usually on or near the inner fender of the passenger side. The line will go from the comp to to the condenser to the orifice tube..you want the line AFTER the orifice tube that goes into the evap (into the firewall) then out and back to the comp.