03 suburban weak air pressure from vents
My 03 suburban has front and rear heat/air. Rear h/a blows fine. Front h/a has issues. My digital controls will switch back and forth fronm feet, face, defrost, etc. I can even hear slight noise as it does so (which I don't think is an issue. What little heat or air comes from the vents is hot or cold depending on what temp you have it on. Temperature is not the issue
Here'* the problem: very little pressure comes through, whether fan is on high or low. When on high, the blower motor is roaring like it'* blowing 100mph, but no air pressure at vents. Before it got to this point, it wouldn't blow on low-med but would blow correctly on high. Then sometimes on high it would make a thumping noise for a few minutes (and fan motor wouldn't be blowing), then fan motor would start roaring and it would blow correctly through vents. But as I said, now fan motor blows, just doesn't come through vents.
I've read about blend doors, blend door actuators, cabin air filters (which 03-05 don't have), but nobody else'* issue seems close enough to mine for me to diagnose.
If you've had experience with this issue and can help, I'd appreciate it. Thanks.