A/C leak on 2011 Dodge Ram

[Rivas55]

I have an A/C leak somewhere on my 2011 Ram that I cannot seem to find. When I add Freon to the system it blows cold for a good amount of time but then it leaks out somewhere and starts blowing warm air again. I did a vacuum test on it and the test failed , indicating I have a leak somewhere but I can't seem to find it. I even did a dye test on the system, shooting dye through the entire system but still was not able to see dye leaking out of anywhere. I replaced the shrader valves anyway as a quick fix but of course this did not work either. I'm kind of thinking a Evaporator leak that I can't see because it's underneath the dash. What do you guys think?

 

[crash68]

If you have used the dye in the system, they make bore scopes you can use with a smartphone, tablet or computer to look into the HVAC system. They're fairly cheap online/Amazon.
The alternativewould be to check auto part stores if they loan out refrigeration leak detectors, anything decent will cost $$$$ to buy.
It probably is in the evaporator but check the connections on the compressor and double check the condenser(coil in front of the radiator). Use a soap bubble spray on leak detector, have the system charged with refrigerant.

 

[Rivas55]

I did check the condenser coil in front of the radiator and did not see any dye at all with my UV light whenever I did the dye test on it.
I will check on the bore scope you can use with a smartphone, thanks for that idea!

 

[PaulTGarrett]

My 2012 has developed the same problem. Charge the system, works for a while (about a week and a half) then no cooling. Since it's been comfortably cool for a couple of months I just unplugged the compressor so I didn't accidentally run it on a dry system. Bad things happen when you keep doing that. Seized up the compressor in my Bronco doing that. When I get ready to find the leak, I'm using dye and nitrogen instead of freon. Heck of a lot cheaper and eco friendly.

 

[CVX20]

Check the drain tube on the firewall with your blacklight.If the evap. is leaking the dye will show there.