1991 Mercedes Benz 560sel • V8 2WD Automatic •

My car is losing freon so I apply pressuer in the system ( 250 in the high side ) just to check the leak location, and for 2 days there was no change in the pressure.(2 days not using the car at all)
but when I start using the car with the AC after charging it with freon for 5days I lost the freon agin.

i still can't found the leak
Benz man
August 25, 2011.

You need to put a UV dye in the system, run the A/C a lot to let it circulate as much as it can and then use a UV light and safety glasses that are designed for finding leaks to locate where it is leaking from.

Aug 25, 2011.
Do as suggested and I would also use a gas sniffer if you cant see any leaks, and check the vents for refregrant as you may have a leak in the evaporator and you will not see this with the UV system.

Aug 25, 2011.