The blower (fan) motor in my 91 classic only works occasionally. heat is fine and the redirect doors seem to be working fine. I dont think this is a fuse issue so I'm looking for some input on where to look.
Thanks
Fred

 

I wouldn't suspect a fuse - they don't come and go. On my '92 Caprice when I removed the blower resistor it was easy to see the problem - corrosion had destroyed it. You can fix it to work in high speed for free with a piece of wire if you're broke.

I would suspect the resistor first and if not that then the motor itself and lastly the switch. Running a wire directly to the motor will tell you if it works or not. Although if the motor is tired it may be intermittent and in working mode when you test it.