Chevy Lumina Heater vent control
My 95 Lumina has a great working heater and AC. The problem is that I can't change to the different vent settings. It is currently stuck on the defrost vents but no matter what vents I select it stays on defrost. Not sure if this is a vacuum problem or do the work on solenoids. To know what and where to look for the problem would be greatly appreciated.