So Quickly blowing (pun intended) through the issues with this Durango. Last one for now is, I am getting now air flow out of my upper vents. The floor ones work great, the defrost work great. Everything switches as it should EXCEPT the upper vents. Can't find any obvious leaks under the hood in vacuum lines (though honestly I don't know where to look for the lines that go to the box that controls the air flow. Also I figure there's probably a main line that goes there and that must work since it's switching between floor and defrost fine. So ideas on how to trouble shoot the upper vents?

 

probably something jamming the diverter door so it cant rotate all the way, unfortunately this assembly is behind the dashboard.

 

Could also be an issue with the vacuum actuator for the diverter door.

 

Finally got back to this problem and was wondering if the entire HVAC assembly needs to be removed to get to this or is there a way to remove a few pieces of dash and get in there to try to unjam it? I can't seem to find a single video or pic of someone messing with the mode doors or assembly. All I see is blend door issues.

as an update. I did verify that my vacuum line to the firewall is fine. disconnected it and the vents defaulted to defrost and wouldn't switch to floor. Reconnected and vents switch from defrost to floor but still no face vents. I looked under the driver's side dash and saw a diaphragm type thing that moves when i switch vents. It moves from floor to defrost. When I disconnected the vacuum line to it , I could manually move it from floor to defrost but in no position did it divert to face. I'm guessing the face vents use a different diaphragm unit?

 

Yep, different actuator for those. It's under there somewhere..... probably hidden where it's impossible to get to.

 

ok, found the right actuator and looking at a bunch of youtube videos I see where the rod goes. it goes over and up to the top of the HVAC box and moves that big door. Well i can feel that it's no longer connected up there. try as i may I can't get in there with the dash in place (even removing a bunch of pieces and covers. There's just no way to reattach without removing the whole dash. Looks like that's the next step.