I have numerous post regarding a/c problems. After replacing everything in the system at a cost of around 3300.00, I'm still having inconsistent vent temps. I mean one minute its 40 degrees and the next its 68 degrees. I'm hearing that my heater door might not be closing all the way. I'm not hearing any noise from it. No clicking or anything like that. I have six vents on my dash and I noticed that the three on the left side have a vent temp 8-10 degrees warmer than the three vents on the right side. Would that suggest there is a heater door problem??

 

Lot of hot air on the driver's side

 

Not sure if this will help, as my Durango is a bit newer ( 2008 ). Where there is the dual climate control for driver/passenger, there is a second blend door, which controls the heat/airflow to either side.

There is the main temperature blend door, the driver/passenger blend door, the defrost/vent door, and a outside air/recirculate door. So four doors and actuators. What your describing sounds like the driver/passenger blend door may be broken.

Where the electric/mechanical actuator attaches to the blend door breaks right off, so the door just starts flapping around. Usually though this issue causes the clicks or noise from the actuator as it "hunts" to find the proper position but never encounters any resistance when the door would actually close.

The actuator may just be defective. I got a used one from a pick ur junk to test mine, but it turned out my door was broken. When I removed the actuator motor, I could see the attachment point flopping around in the hole, a it was no longer attached to the door.

To repair the doors often requires removing the whole heater box, which requires removing most of the dash and is expensive. I drilled some access holes and just screwed the door in position I needed.