Well I'm not sure its fixed yet. My wife drove it to the gulf yesterday. She said about 20 minutes into the drive the vent temp was blowing 75 degrees. She turned it off and let the vent continue to blow and she said it got down to 42 degrees. I don't even understand how that is possible. I'm going to buy me a set of gauges so I can look at the numbers on the low side and high side. The other day the low side was 30 and the high side was 450. Does that sound correct??

 

My immediate thinking is one or more of: clutch not functioning/intermittent, expansion valve issue, PCM is not correct, sensor is not correct or wiring. If your mechanics have checked all the mechanicals like clutch, expansion valves, lines, etcetera then I'm betting it's something electrical. Doing more testing on the mechanicals ~might~ give you an idea of what's wrong but I'd skip over to electrical side.

Have you had a scan-tool attached to print out anything else that could be wrong? It isn't that far of a stretch that everything is okay except the PCM or some other sensor that is throwing things off. PCM has to process all those sensor readings and such to turn things on/off so it all works correctly. Durango's do have some wiring issues too.

And then there are the blend doors which could be mechanical issue or electrical. But AC gauges aren't going to troubleshoot the doors; have to check the electric resistors and such on those and then check the control panel and then check that the doors respond appropriately and accurately.

As far as pressure readings I'd have to check the factory service manual and it depends on elevation, outside temp, rpms, and some other stuff. I want to say the hi side number is a bit high from my readings but not much. Another thing to consider is if the rear AC was on/off before the temp jumped or not.

I think my issue is easier: Either bad high side valve or rear unit is leaking somewhere. So I don't have the same issue to really narrow down for you to check this or that.

Hope this helps.

 

I have had numerous ac problems in my 2005 durango over the last few years. I also had a leaking evaporator. They had to remove the dash, and replace it, and I had them do a heater core while they were in there. It worked fine for a while, then After driving on the highway, it starts blowing hot air.

After doing considerable research about this, I found the likely problem is the Vent/Blend Door or Door actuator. The Blend Door actuators apparently have been a chronic problem for dodge. The keyed end that connects to the actuator gets brittle with age and can crack or break. This allows the actuator to rotate without opening the blend door, or it can skip a notch on the blend door and it wont close off all the way letting hot air from the heater core blow in mixed with the AC. Mine does this in both the front and rear air box. Usually not at the same time, but over a 3 hour road trip they will both do this off and on. The only way I have found to get it to go back is to turn the system off for a few mins or cycle the vent **** to defrost and heat and back to cool and max ac. Then after another 20-30 mins it happens again.

The only way to fix it is to pull the dash (Again) and replace all the vent doors and actuators. Its such a costly repair that I dont think its worth it. So I have been living with it for a couple of years.

Now I have a new problem very similar to yours. It will cool fine while im moving, but when you stop at a light or park, it starts blowing HOT air. I traced this down to a bad Electric Fan on the condenser. I have the repair part now and am trying to figure out how to get the damn thing out so I can put the new on on.

 

Another thing that I have found is an electric valve with the heater hoses connected to it in front of the passenger front tire. I am told this valve stops the hot water from going to the heater core when you are using the a/c. I clamped off the hoses and my vent temp went down to 49 degrees sitting still. So I think this valve might be bad. It cost about 150.00 to replace. I will replace it next week and update.

 

This valve is actually an auxiliary water pump. I'm trying to find out more info on it and what it does but I think it pumps hot water to the rear of the vehicle and back to the radiator. mine is not leaking but when I clamped it off the vent temp went down to 49 degrees. I'm not sure if this has an affect of the a/c performance.

 

Okay so first you need to replace expansion valve next replace the orfice tube after that you’ll need to do a dye test to find out where the leaks are, it’s the orfice tube 90% of the time and no one ever changes it. Any kind of blockage in the orfice tube will back pressure and blow a hole in the system at the weakest point, this is a high pressure system people