I have had my 98 Ram QC 4x2 5.2L for 2 and a half years. The a/c compressor and condensor were replaced by the dealer in December when I bought it. It holds a charge, I have used a guage to test it and it is full of refrigerant. The compressor cycles, but it produces no cold air. Since it has held it's charge for 2 1/2 years, I know I can rule out the compressor/condensor/evaporator. I am wondering if anyone knows, no longer having any of my equipment from my mehanic days(aside from an a/c pressure guage) if there is a common problem that I might take a whack at next? I was thinking the reciever/drier might be the next item to rule out or replace. As I said, the system cycles normally.

 

Sounds like you may have a clogged orifice tube which is not allowing the freon to cycle through the system properly. Do you know someone with a real set of gauges? They can check high and low side pressures and tell you whether or not it is clogged. How long is the compressor cycling for? Is it holding at the correct pressure per ambient temp when the compressor is cycling? Lots of variables there. Let me know what you do or don't have access to and I will try to direct you in the right direction.

 

It cycles every 10-15 seconds. I'll get the exact pressure on the high and low side tomorrow. When the air temp is very hot, above 90F it cycles longer, about 20-30 seconds like the a/c is running normally. It just isn't blowing cold at all.

 

OK. It sounds like you are actually low on freon. It will still show full when there is air in the system because the air is taking up the space where coolant should be. After you get pressure numbers we will know better.