1994 XJS 4.0 L. I guess if you could have AC problems I had them. Both the high side and low side ports leaked. No problem on the low side, you can get that anywhere. The high side however in my case leaked at the solder joint. Thank goodness we have a company in Colorado called "Maxair" who could rebuild the hose. But it didn't stop there. The condensor was covered in oil streaks from multiple pin holes.

Took it my radiator shop, it failed a pressure test.

https://i.postimg.cc/tgGhWzFt/condensor.jpg


Well, what now? Turns out the compressor was covered in refrigerant oil on the bottom. So new compressor, for the 4.0l these are easy to come by.



Ok now the system has held vacuum for three days, time to recharge. Not so fast.

Evap seals are toast. Out comes the dash and everything to replace some o-rings.

Where are we today? Just a smidge above 45 in 100 degree heat. Do I regret it, yes.

 

Feel your pain. Still troubleshooting a problem getting vacuum to the defroster vent to get the center ac vent working. Had to replace the condenser to start with. So far that was the only easy task.

 

For years my AC works great at first start, and then it will lose its ability to cool the cabin if I stop to get a meal, shop, or whatever. But managed to fix the issue by using a MighTvac.
Keep this in mind when you sort things out. The heater valve closes when vacuum is applied via the sytem when I switch to AC, but as soon as I shut the car off in a hot parking lot after driving for some time in hot weather, the heater valve will open when the car is shut off after a drive. This allows hot coolant to enter the matrix and when you get back in, the AC now has to battle the hot matrix before cool air reaches the cabin. So what Ive done is, plugged the vacuum line, pulled vacuum with a MighTvac on the valve and left it in the engine bay, for summer purposes. This essentially never allows hot coolant into the matrix. On cool nights I release the vacuum and let the coolant flow. Anyway this should help keep your AC cooling the cabin without having to cool down the matrix first. Keep this in mind. BTW I live in SoCal and 110 is becoming the norm during heatwaves. Manual valve would be the way to go but, with deserts it gets hot and cold in both extremes.