About a month ago my AC on my '99 Dodge started blowing hot so I added a can of R-134 which cooled it off briefly for about 2 hours. I then added another can while paying attention to the compressor which would kick on and shut off after about 3 to 5 seconds and the system blew cool air for about 15 minutes. In speaking with my mechanic he feels it is the Evap. Core and wants $800 to $900 to replace it. I have read many of the posts on the forum relating to AC issues and at this point am planning to have Pep Boys do an AC test on it then possibly put a can of leak stop in it & recharge system. I welcome any feed back or suggestions on what the issue is and the best as well as most cost effective way is to fix the problem.

 

Have whoever is working on it install UV dye. and charge the system, if they dont know what it is, they probably should not be working on cars. Anyway install the dye get a uv dye light, and go over every visible area of the truck that has to do with ac ie compressor hoses, connections, condensor. If nothing is found see if you can get your hands on a ac leak detector. put it in a bottom duct of the truck, turn off the blower wait 5 seconds and turn it on, if there is a leak, the refrigerant would build up in the heater box and then get blown out. Have fun. BTW i just put core in my truck, that was a fun job

 

Evaporators are a common failure on 2nd Gens. I'm on my second one, was diagnosed as leaking using uv dye as discussed above. Hopefully yours is leaking somewhere more accessable, like a hose under the hood. Good luck.

 

Thanks for the advice and I will be exploring every possible avenue before replacing the Evap. Core.

 

My evaporator leaks, but the uv dye was a waste of time, money and refrigerant. The tech had to use a sniffer (leak detector) to detect the slight amounts of freon leaking from the evaporator. Of course if you are putting a can of refrigerant in and only cooling for a few minutes, I suspect a rather large leak. The uv dye might do the trick.