I've got an intermittent problem with the air blowing out the vents ('94 Delta 8. It'* happening more and more often.

When I have the air on out the upper setting, every now and then I can hear a flap close behind the dash and the air is redirected out the dash defrost vents. Sometimes it corrects itself a minute or so later, sometimes not. If I wait long enough the vent will close (or open, not sure) and the air comes out right again. The indicator lights on the air panel don't change.

This is aggravating in this Texas heat. Has anybody had this problem, and if so, do you have any insight on what I can do to fix it?

Thanks

Air blowing out the defrost openings is the default mode when the HVAC control head fails. Maybe its starting to go. If so, it will start to happen more frequently.

I just went thru an almost exact problem with my 1994 LeSabre. Mine would blow thru the defrost sometimes, and then it would "correct" itself and blow thru the correct air vents. All other functions worked properly.
I was stubborn and kept trying to blame it on the vacuum distribution under and behind the glove compartment. Bought a new one, same problem.
Went to the local pull-a-part and found the correct control head in the dash, this fixed the problem.
Mine was not the climate control, just the regular electronic push button. Also if I remember correctly model years 1992 thru 1995 on the Buick was what would fit. I would guess yours will be the same.

Joel

Well, looks like a trip to the Pick-n-Pull is in order. I had heard that if the control head is going, it'll be a real bear to dig out and replace.

Ah well. I've got a good lead. Thanks guys.

By the way, this is exactly what it'* doing. More and more frequently. I'd guess you've nailed the problem. I'll update the thread when I get it replaced.