but.....not cold at all. Any ideas? It's my son's 98 Cavalier and he has a 1 yr old boy....TOO HOT for the little guy!
My only previous experience with these symptoms was on a 79 Cordoba. It had a flapper door which would not open. Turned out to be a bad diaphram on that flapper door, that would not allow cooled air into the cabin. I don't know Cavalier systems though.......
How do you know it is charged? The 98 Cavalier uses a V5 variable displacement compressor and does not cycle. The charge amount is very critical on them. They are also very prone to compressor body leaks. Feel the AC lines where they exit the firewall. Both should be cold and close to the same temp. If they are warm, or one is cold and one is warm, the refrigerant charge is low. If both are cold, you may have an issue with the Blend Door in the HVAC case inside the car. You really need to know the High and Low system pressures on this system AND the actual amount of refrigerant for troubleshooting. It's common for the control valve in the compressor to fail and the only to know for sure is to compare the pressures with a known full system charge (+or- about 2 oz). Edit: If the control valve is bad, it can be replaced separately. You don't need to replace the whole compressor.
I just used the gauge on the charging line. I know it's not the proper way to evaluate charge but has worked for me in the past. The lines never got cold or frosty.... Thanks for your input.
Without actual High and Low side gauge readings it's just a guess, but I would say the control valve had failed and the compressor is at minimum stroke. Because that valve is sensitive to the proper charge you need to evacuate the system and charge the proper amount (by weight) then check the performance. If it still doesn't cool and the pressures are near equal, the valve has failed. There's no other way to test it.
If this is a retrofit you may have to change the metering device(orfice). 134A Pressure/ temp diff's are close to R12 but not exactly the same. As stated above you really have to have high and low side reading to properly diag. the system
Two possibilites I might suggest. First, was the system evacuated before charging? Was the orifice tube and accumulator replaced? A compressor failure will scatter debris in the system, and if the orifice tube and accumulator are replaced, the new tube can become restricted due to the debris recirculating in the system. Are you sure the compressor is running?
