My A/C was/is blowing hot. Took it in to local repair shop and a valve on the high side (right above the compressor) was bad. Fixed, filled and blew cold. One week later and warm/hot air again. Brought it back in and the dye was around where the valve was and the mechanic said it must be a bad gasket. Replaced that and one week later I have warm air again. No signs of any dye leaking out along the lines or on the condenser. Is it possible that the evaporator is bad and how can you tell? Any other suggestions on finding the leak?

 

If you have a leak in the evap, you usually can see dye at the drain of the HVAC box. If you are not familiar with the drain, it is a small stub coming thru the firewall on the left side, near the bottom. You will need to crawl under to see it. Check the condenser too, might of caught a rock or something in the front. Based on history, I would look closely at the evap.