A small diameter vacuum tube that controls the vents becomes brittle and breaks. Open the hood and look for a tee connection behind a canister on the passenger side. This tube runs over the motor and connects to a port just to the right of the throttle body. You will need to remove the air intake cover to get to it. Takes 15 min. to replace. (Only if you do not have AC) The port has an elbow that you just won't have access to. (GM doesn't want the public fixing anything due to union design greed and corporate roll over, and they all wonder why they are history) Much easier than opening the dog house. Unless you have AC if so, hey change the plugs to 3 point ignition gap plugs and give it a new lease on life.
Leak in exhaust system perhaps exhaust manifold being sucked in through air intake (grid at lower end of windshield)
Air conditioner drain line stopped up or windshield seal leak that covers 99% of the reasons
It is probably comming from the windshield. Have someone run water on the windshield and check it inside with a flashlight.
Out of time.
Have the windshield removed and retapped.
Rule of thumb, if you can feel the scratch with your fingernail, it ain't coming out, replace the windshield.
That is condensation and it is normal for water to come out of an air conditioner in the back of it.
You probably have a bad heater core. Find where it is coming from. You probably have debris stopping up the drain below the windshield.
Put a large plastic trash bag over it on the outside of the house and secure it with duct tape.
It have battery
A smell coming from a reverse cycle air conditioner may be a signal that the filter needs to be cleaned. A smell like engine exhaust might be present if the air conditioner motor is in need of repair.
I get hot air coming out of my air conditioner on the passenger side, while I get cold air coming out the drivers side. Can you tell me why and how do I find the schematic to fix it?