Howdy! So here's the run down.
2001 Cherokee sport 4.0 142000 miles...runs Amazing

The air conditioning is obviously not working. IT will blow cold if I put freon in it, but unfortunately it's leaking out or something and gets hot the next day. I have had 2 mechanics check for leaks as well I have also. We cannot find one. It held 90lbs of pressure all day long while running during test. Then somehow lost it by the next day. The compressor, accum. And orifice have been replaced. The evaporator core is not leaking either. I just looked up under the vehicle to check the condenser and don't see any leaks. So the A/c stays cool then blows hot the next day and no leaks have been found anywhere. Anyone have any ideas? I live in Texas. It's hot. I was stuck in traffic the other day and literally could have had a heat stroke. Lol the whole 55 mph with the windows down doesn't work very well in Texas....it just dries your eyes up and burns your skin lol

 

maybe use the dye in the system. My 99 was leaking through the hose from the compressor to the accum. Looked like a sprinkler hose -- once I found it, it was hidden inside the outer cover.

No traces of oil anywhere? maybe a line on oil across the inside or the hood, above the compressor.

 

I have seen no trace of leaks. I used the dye last week and this morning at 5 am......still nothing.

 

If your mechanic has a dye, he should have a sniffer.....it can tell where the freon is leakin from .....try that next time.....

 

check behind the compressor pulley with a sniffer....that leak is hard to find sometimes...also sometimes making a solution of dish soap and water and spraying on all the hoses and fittings will show any small leaks as fine bubbles...good luck

 

use more pressure and use nitrogen to find leaks go to your local hvac supply house and get some liquid leak detector spray down in a shaded area with motor cool give it a few and start looking using refrigerant for pressure rarely works