My 1995 prizm heater ducts were invaded by rodents, lot of noise of leaves, etc. when fan is turned on. How do I clean this out?
You’re going to have to take the blower motor assembly out, take it apart, and clean all the junk out of it. This will most likely involve dash disassembly. That is not a fun job. I don’t envy you.
It also seems that the doors or flaps are jammed when moving the heater dial from floor to dashboard to defrost (I get no air flow to defroster). Any advice?
First approach find and clean out cabin air filter…that may solve your problem…it sits above the fan, at least, in my car.
I’m not sure a '95 Geo would have one.
Re: the doors - - yeah, that can happen. Once you get the blower out, you’ll be able to poke around in the vents to get any material that’s stuck in them out.