I’m wondering where I might find a schematic for the vacuum tube system? My 2006, 4.0 has always seemed to have issues with the airflow. When I bought it four years ago I could tell the A/C was working because I could feel cold air in and around the dash yet no air was flowing from the vents. I wasn’t initially aware that the vents and such were controlled by vacuum pressure. On arriving home I opened the hood and found a good-sized section of tubing on the driver’s side of the engine that was actually melted through in several places. There was a part number on it so I ordered a new loom of tubing and had it installed at the shop where I bought it. After that the A/C air flowed but not very well.
Now the heating is working about the same. Air flows but not well. I can’t help thinking that there is some leak that is causing an inefficient opening and closing of an air vent. I know that the blendor under the glove box works just fine. Is there another vent back up in there that could be causing a problem, possibly due to a vacuum hose leak somewhere? Or maybe one of the vac tubes is disconnected?

 

Or maybe one of the vac tubes is disconnected? This is where I'd look.
Perhaps the vacuum is fed to a diverter controlled by the **** on the dashboard...and that diverter is cracked?

 

George,
My central question remains. Is there a vacuum schematic available as a reference? The problem is being able to find all the vac lines. And I’m not sure of the source of vacuum pressure to begin with.

 

George,
the problem as I see it is that there is such a jumble of at least similar looking tubes. Where do you even start?