95 A4 Convertible. I bought the non running car in January and had to do quite a bit of work to get it running (had Jeep for cold weather) I now have it running good but when I tried the A/C it blew hot air. The compressor clutch does not engage so I assumed it was probably just low on refrigerant. When I attached my recharge kit to the low pressure side of the system it read something like 120-130 lbs. According to my guage it should be around 50 lbs.

What would cause the pressure to be so high? Did someone just overfill it way too much? Any suggestions on how to proceed with diagnosis and/or repair?

 

Bring it to someone who has an a/c machine that can vacuum the system then re-pressurize it. When hooking the machine to it they should put 2 lbs of pressure as stated on the big silver a/c canister.

 

Taking it to a shop and asking them to fix it is certainly an option but it is not the type of suggestion I was looking for when I posted the question.

I have a vacuum pump and can excavate the system myself. However, I thought that this may be a waste of time/money if the high pressure is an indication of some other problem in the system.

What might be causing the high pressure on the "suction side" of the system? Is overfilling the ONLY thing that might cause this or are there other possible causes that I should consider if/when I evacuate/recharge?

Thanks, Joel