Sounds like it could be many things. I didn't pull a vacuum since the system still had pressure on it when I pressed the schreader valve in. I bled the pressure out of the system until it got very low, but not totally evacuated. The system has a low pressure switch that kept the compressor from engaging the clutch at low static pressure. I know I got about 18oz in the system last night. We are going to drive the car in the heat and see what it does, a 450 mile trip today. We don't know the history of the car but know that it has been in a front end collision before since the core support is deformed and the hood has been replaced. Maybe the condensor is mangled, don't know for sure. As a last resort I may just replace the compressor and all the hard parts and recharge with 134a to upgrade it. Ebay lists the compressors for $145, a lot better than $340 at Autozone and $570 at Oriellyauto.