TestPoint

Working on my brother's '95 XJ with air conditioning problems. Worked fine a year ago but spent some time 'resting' needing a new engine. Now has one.

Vent temp is ambient air temp. When first connected gauges read 30 psi static pressure. Compressor clutch does not engage. Added a half can of R134a and got clutch operating. Low pressure side 40 psi, high pressure side 40 psi. Added another can and low side now 50 psi but unfortunately, the high side reads that also. High side hard tubing gets hot. Low pressure side sweats. Vent temp still ambient 80*.

Unsure that it needed another can but I had several. Everything still reads 50/50 psi. Lots of condensation water out of the drain but vent still at ambient air temp.

Since the high side gets hot my best guess is a clogged expansion valve.

Second guess is an internal leak in the compressor.

Comments and suggestions appreciated.

OldTires

High side is supposed to get hot until it hits the expansion valve, which then gassifies the R134 liquid. This gassification causes the temp drop in the R134.

So before the expansion valve it should be hot liquid, after the expansion valve is should be cold gas.

You need to have the system evacuated by a shop, then vacuumed to find leaks. Fix leaks, vacuum again, and then fill with proper amount of R134.