It's been really hot in SE PA over the past few weeks and "Duchess'" A/C unit has been getting a workout.
But the air temperature through the dash vents -- Left vent, Center vents, Right vent -- is completely uneven, differing by as much as 15+° between the far left and far right vents.
The refrigerant pressure and level both test fine, and cold air is coming out of one of the vents. (But naturally, it's on the other side of the car from where I sit.)
I suspect the left side duct hose is torn or loose from its mount.
How hard is it to view and/or access this hose? Can it be done from under the dash? Does the dash have to be removed? Is there an illustration of the hose routing I can find on line?

 

Have you changed the cabin air filter lately?

 

I hadn't given that much thought cause I put a new one in 16 months ago, when I first got the car.
They don't clog up that fast, do they?

 

Not usually, then are you hearing any clicking noises in the dash area indicating the blend doors aren’t functioning properly?


If you remove the waterfall panel, can you see the passages under the dash?

 

Not much to see under the dash top cubby

 

Oldblue. Sounds like you're trying to imply taking the dash out is a simple task. Well, it's not.
AND. You would have to mess around with the airbag SRS system which can be dangerous. Not something for the novice to be working on.

 

Statement withdrawn, thank you FMG !




There’s not much to see under the dashboard top either. As FMG points out, the air bag has to be removed, I do not recommend that !!

 

 

How bad was the old filter?

 

The old filter had seen better days; I suspect it had never been changed.
Because of your & Oldblue's suggestions, I'll take a look at that filter later today.