case310350

have a 97 dodge, the a/c is blowing slight cool. when I feel the line by the low pressure its very cold. checked the psi is 25 to 30 which is about right. compressor sounds like it on for 10 sec then off then back on. Not sure how to troubleshoot this problem. the line before the expansion valve is warm to hot, which I think it should be. any ideas.

oh one more thing, when i move the temp **** in the cab it appears to work, as I can vary the temp, just can't get cold air.

HotRodTodd

You are low on freon more than likely.
What is the high side? What is the low pressure when the compressor cycles off?

cody_d

25-30PSI seems a little low, if I remember right from recharging mine it's supposed to be around 35-40ish PSI.

If your charge is good, how is your air flow? If you dont have very good air flow, your Evap. coil may be plugged/covered with leaves, or that cotton wood crap.

JJK98CTD

134a 40* evap coil = 35.1 psi on low side. Will be little bit higher if heat load. Head pressure could be around 250 psi or higher depending on temp. I helped my budd replace the ewvap coil on his 2000 and it wasn't fun. It was clogged with oak leaves and other crap and the leaves help rot out the coil when they were breaking down creating a acid. and it eats thru alluminum.