I have converted hundreds of Fords to 134A. Some work great without any alterations except a clean charge.
If one is acting like yours I suspect you will need to change the orfice tube and the dryer. The replacement orfice tube must be for 134.
I use ester oil in a Ford, it seems to wrok better. Remember the 134 charge is about 23% less refrigerant than R-12. You must charge by watching the gauges on both high and low sides. It is very easy to overcharge and the cooling will be reduced. Even a couple of ozs will reduce cooling.
If you car is loosing refrigerant and it is on the suction side (low pressure) it will suck in outside air through the leak and your cooling will be greatly reduced.
Fix the leak and stay away from the $7.00 can. It is mostly propane and dangerous to uses in addition it will corrode your system. There are no cheap solution to referigerant as R-134A is about $7.50 a can but it goes up as gasoline goes up.
Tuesday, December 1st, 2020 AT 12:16 PM