Just like it says, I put the selector to defrost, it works fine, set to heat on the floor, it works fine. But if i set it to bi-level, normal, or max, i get no air from the dash vents.
I took one of the center vents out of the dash and reached down into the duct. There was a door there that opened when i pushed on it. It stayed open for a few minutes, and then closed again, leaving me with no air from the vents yet again.
Any ideas as to what is going on?
*EDIT*
Ok, after extensive searching through the many archives of unresolved threads....(argh), I went out and did some more testing of the HVAC switch in different positions.
1) With the switch flipped to 'cold' I hear an audible hissing coming from the vicinity of the control switch.
2) Set temp selector to 'hot', switched to bi-level = nothing
3) Kept at 'hot' and set switch to 'max'. Felt air coming from vents. Changed temp to 'cold'. This made vents work.
4) Drove around for appxly 10-15 min, then vents stopped working again.
5) Changed from 'cold' back to 'hot', then back to 'cold' and then they worked again
I ask, WTF?

 

Sounds like the HVAC control switch is taking a dive...Maybe the vacuum lines behind it. Remove the radio first to help access the HVAC control. Good Luck