While driving straight at highway speeds, I heard a loud whistling from the engine compartment and then saw a small amount of smoke come from the under the hood area. No lights came on dash. The A/C was on full blast at the time (its summer here in Louisiana). Shortly after this, I realized the A/C was blowing hot air. When I first started to try to diagnose the issue, I checked the AC diagnostic codes. 23 and 43 were displayed. Then I checked the pressure from the shrader valve in the low pressure side. Empty. Since it leaked out so quickly, I assumed a rock got kicked up under the car and punctured a rather large hole in the system somewhere. So I started to inspect all around the system to try and find a hole or leak. When I got to the compressor area, the joint where the low pressure hose side connects to the compressor, was visibly unattached to the compressor. It was come off due to the screw that goes into the compressor becoming stripped. At this point I figured the compressor shut down automatically because it detected a lack of refrigerant. I hoped that if I found a matching screw (which i did) and reconnected the hose to the compressor, stopping the leak (which I did) that at this point I could simply add the correct amount of refrigerant (the kind with no additives or oils) and that the compressor would fire back up and my AC would work beautifully again. After doing all this, the compressor did start right back up again. I saw movement again in the sight glass (with no bubbles). Yet after running the AC, its not blowing cold air. This is where I'm stumped. Any tips on what to check for at this point?
you can't just bolt it back together and throw refrigerant in. In order to do it correctly, you have to use a vacuum pump to get all the air out of the system (also handy for detecting leaks if it wont hold a vacuum). The oil for A/C absorbs water and air and the air in the system changes the evaporation temperature of the refrigerant. Pressure gauges are useless with air in the system also as you started with ambient pressure and further pressurized it vs starting with a vacuum and adding until the correct pressure is reached.
