Anyone know what would cause this? When I change the control from defrost to vent to floor the tone of the blower changes like something is happening but the air still only blows from the top with good pressure and slight pressure coming through the vents and the floor. Whats wrong with this thing.

 

I may be having the same issue with my truck. All four fan speeds work, and it will blow a/c and warm air when set. But it only comes out through the floor and the defrosters on the top of the dash by the windshield.

ideas?

 

I will find out for sure in a few days when I install my stereo and have better access to it but I think from researching this myself on the web that there is a gear that is run by an electric motor that actuates the diverter door and that it strips off. I am going to see if I can locate it when I have the dash tore apart to do the stereo. I will keep you posted but so far I have asked 2 questions on this board and gotten no response from either of them.