A/C is not working at all. Please Help

[blackngoldrules]

My wife has a 2002 2.4L cavalier. The A/C is not working at all for her. How can I test the compressor to see if it's gone bad? I was hoping it just needed recharged but I connected a gauge to the low pressure port and it appeared to be full of refrigerant. It looks like the A/C compressor is in a real pain in the a** place in her motor so if it's that then I have a real project ahead of me. Anyway, thanks for any info concerning this!

[brcidd]

First, you can't just connect a gauge to a system (without it running) and determine "it is full" and second- the number one failure mode of mobile a/c systems is loss of refrigerant due to a leak- that V-5 compressor on your car is very durable- but it can't perform without the necessary refrigerant to pump- refrigerant is a condensible- more refrigerant does NOT mean more pressure- it is NOT a compressible- like air in a tire!! So your death kit gauge reads okay-- but you can only determine that when the a/c is on. A system with 4 ounces of refrigerant will have the same pressure as a system with 4 pounds in it- statically with the a/c off.....so my money is on the fact you need to find and fix your leak and put in the proper refrigerant charge..

[Hungrycat7]

You can purchase dye to put into the system. You can use a UV light or black light to see where the die is coming from. Then just go from there! Usually it is a small pin sized hole that you would never find without the dye!

[blackngoldrules]

Originally Posted by brcidd

First, you can't just connect a gauge to a system (without it running) and determine "it is full" and second- the number one failure mode of mobile a/c systems is loss of refrigerant due to a leak- that V-5 compressor on your car is very durable- but it can't perform without the necessary refrigerant to pump- refrigerant is a condensible- more refrigerant does NOT mean more pressure- it is NOT a compressible- like air in a tire!! So your death kit gauge reads okay-- but you can only determine that when the a/c is on. A system with 4 ounces of refrigerant will have the same pressure as a system with 4 pounds in it- statically with the a/c off.....so my money is on the fact you need to find and fix your leak and put in the proper refrigerant charge..

I guess I should have been more specific on how I used the gauge, but I just assumed you guys would figure I did it the proper way. I never said how I did it, so you can't just automatically assume I didn't do it properly. I DID use the gauge with the car running and with the A/C on at full blast maximum. It read 40PSI on the gauge. It's a gauge that came with the R134a that I used to put in my truck when I recharged it. Since it got that reading, that's why I figured there had to be something else wrong. I'll take Hungrycat's advice and still see if their might be a leak somewhere. I hope that's all that it is, but if it keeps reading full everytime I check, then I think it may be something else. Hope I'm wrong. Thanks for the advice.

[brcidd]

Air in the system will show a high low side pressure- so if you allowed air in or charged without pulling a vacuum last time it was filled- it will "fool" the system and your gauge...

Knowing the high side gauge reading would be a big help.....