Help! Front vents won't work

:banghead: I have a 93 lumina. Now, among the many issues I've had, this has been the most puzzling. My blower fan went up. It was replaced a little while after and now my front vents won't work. The defrost and floor do! Does anyone have an idea where to go from here?:uhoh:

Most common problem is loss of vacuum supply to vent actuators- due to a vacuum leak underhood- On "W" cars such as yours- look for the black plastic vacuum line to be corroded, broken in two, cracked etc- right by the battery- as it goes down to the vacuum reservoir in front of driver's side front wheel. For safety reasons, the air comes out the defrost in case of loss of vacuum supply- Plastic supply line can be fixed by splicing a small rubber hose over both ends after trimming the plastic-- the battery gases work hard on those lines--- I have also seen the battery sitting directly on top of that line on a "W" car.. Hope this helps....

If this has happened only since the blower motor was replaced, then it is probably a pinched or loose vacuum line in front of the dash.