2nd Gen Non-Engine/Transmission A/C Cooling On Again Off Again

[CHill]

I am having a problem with my A/C unit cooling fine one minute and blowing hot the next. Once I get moving and the RPM go up it cools down again. It might do this once a month or ever hour. I've been knowing that I had a small leak for some time now. But it was cheaper to put a can of R-134a in every 3 months or so than spend the money to fix the leak. I was thinking it was leaking out the evap core but now I think it might be a bad compressor. So I went to do the one can thing and I usually just hook up the low pressure side. This time I hooked up both sides and come to find out the high pressure side of my system is only at about 50 to 55 psi. The suction side when full I run about 50 psi. With such a low high pressure side I am thinking many the leak is in the compressor seal and the compressor is just shot. I live in south Louisiana so the A/C gets used even during the winter months and the truck has 190,000 on the original compressor. Any help would be,,,,,,,, well helpful.

 

[ThrottleJockey]

What's the pressure on the LOW SIDE only with the AC and engine running?

 

[CHill]

It ranges between 40 and 50 PSI.

 

[ThrottleJockey]

Do you realize your user name is 'chill', and were talking about A/C problems?



I had the same thing happen. I used a can of r134a with a leak sealing additive. Did the trick, did the same thing on my 94 Grand Cherokee.



The compressor would cycle alot and the pressure would bounce back and forth from 30 to 50 psi. It was 65 psi just sitting overnight and checking the low side with the engine off.