Ever since I bought my GTA (2 years ago) I just figured the ac was shot since it didn't work. Well, yesterday I bought two cans of "high mileage" 134a and decided to tinker with it. I filled it to the proper level according to the gauge and the compressor kicked in, but the air is still warm. My friend was sitting in the car and he said it got cold for a few seconds and then went back warm.

I thought maybe I had overcharged it so I let some back out, but still warm air. I do notice the compressor and one of the lines coming out of it get very hot (the other one doesnt get cold). Is that normal?

Maybe the compressor needs oil? I assume if the compressor is bad that it wouldn't come on at all.

 

Did you do a complete 134 conversion or simply add it to the existing R12 system?

JamesC

 

It had already been converted before I bought it. It has the 'quick connect' port.

 

Un less you evacuated the system, it is probably full of air. Otherwise you may have a clogged orifice tube.

 

You have a restriction somewhere in the lines..

 

Use an infared thermometer to check temps at the inlet and outlet of the condenser. Should be a difference of about 25-30 degrees. If not, you either have an air flow restriction(leaves and crap) between the radiator and condenser or low charge. R134A has very small molecules and will leak through even a tiny opening.

 

I want to make a word of note.....check the compressor to make sure the compressor says r134a..... Just because the quick disconnect ports are there does not mean it was retrofitted. I've heard that the r12 lines do not meet the ISO requirements that r134a has, therefore can cause refrigerant to leak out of the lines as well.

Make sure you left your system in a deep vacuum as well. If you drained it, and then just added r134a....doh. You need at least an air compressor, and a cheap vacuum unit with manifold gauges. Evac it for about.... 30-45mins to allow a very deep vacuum free of moisture and as much air as possible. Then turn off the connection to the vac unit, and make sure your system at least holds vacuum in the lines. If not you have a leak.

 

I think I'm just going to take it to a shop.

 

Ryan makes a good point. The small molecule size of HFC R134A requires much better sealing than the old CFC R12 systems provide. Newer hoses are made from a more impervious material to prevent seepage. Many shops will perform cheap retrofits using adapter valves and a quick evac of the old refrigerant. Unless the system is carefully checked for leaks after charging using a florine detector, it will probably lose its charge very quickly.