When my truck was 2 1/2 yrs. old with only 29,000 miles on it, it had to have the entire a/c system replaced by dealer. Now that its just barely out of that warranty, with only 35,000 miles on it, the air is dying again. The air fluctuated between cool and cooler, but warming overall (the higher the fan, the warmer). We checked the low side, pressure: it was 40lbs at 110+ degrees, chart showed it should be 55-60. We put one mixed can of 134 in and it seemed more consistently cool instead of widely fluctuating, but then on my way home, it blew warmer than ever!

Any ideas of what we could check?

TIA

 

If you just put a can of R134 in and it only made a temporary improvement, you’re probably looking at a system leak somewhere. If you want to check for the leak yourself, get a UV penlight and you’ll be able to see the leak. Don’t forget to look at the drain too, because if the evaporator is leaking, it will show up there.