In my 2001 Pontiac Sunfire, I cannot change the vents that the air flows out of.

The air is blowing fine, but I cannot select a different setting for the air to blow differently.

When I turn the knob, the air blows the same on each setting.

What do you think the problem is, and how can I fix it?

Thank you so much for helping so many people every day!

well, either the control unit is bad or the actuator that moves the vent blend doors, and it takes a dealer scan tool to figure that out without just pure guessing