So I was leaving work today and its pretty frigged out so I try to change my heat to the defrost setting and it wasn't letting me put it in position so I put a little muscle into it and now no matter what setting I have it on it only blows out the front vents.
I've had the same problem last winter for a brief moment, now it's starting to do it again on and off. So you're not alone
Remove HVAC panel, there is a linkage back there, possibly broke off of the HVAC control, or at the mode door
- 2004 Cavalier - 124k, owned since new
Broken off are you sure? As I said it happened before and went away, only to return in cold weather.