No air flow?
Check for vacuum leak either under dash or at engine compartment
Maybe bad vacuum diaphragm under dash
Maybe bad selector control
The air of your Chevy trailblazer 2004 blow out of the front vents when the air conditioner is on because the air condition is faulty and it needs repair.
they are photocells....they adjust the headlights from daytime lights to headlights when it gets dark out and vise-versa
Under the hood in front of the transmission dip stick is a vacuum line. If it is disconnected or split it will make the air vents not work. If that's not it check your fuses.
yes
The 1984 Buick uses vacuum lines to change air flow from defroster to ac vents. Check the entire vacuum system for leaks.
90% clean your dryer vents,repair any torn screens!
There are two hidden screws in each of the air vents. After these are removed there are more obvious ones under the dash that need to be removed as well. Hope you find all of them.
There may be something blocking the deflectors from sending air up there.
If the heat selector will not switch from defrost to the dash or foot vents on a 1992 Buick, it is possible that the cable connected to the vent is broken. When the selector is moved from defrost, a cable opens the other selected vents on the heater.
I had a 92 PA and needed to get to the instrument panel. If this is all you want t to do, look for two screws in each of the air vents. These need to be removed plus the more obvious ones under the dash. Hope this helps.
Your front blower motor has gone out. There is a front and a rear blower motor.
The moveable "baffle" inside the dashboard is not redirecting the air flow as it should. It's operated either by vacuum or an electric motor, in either case, repair is going to require the removal of the dashboard.