Air ducts


#1

I have a 2000 chevy astro van. and the air/vent adjuster does not work. it is stuck on the defrost vent setting.what changes the direction of air flow


#2
Do you mean you can't move the lever or do you mean you can move it, but the air flow does not change.  

My guess is you have a vacuum issue and you will find a loose or split vacuum hose somewhere.