I took my Fiero for a drive today, and when I put on the heater fan, it sounded like a dead mouse was flopping around inside the blower housing, and it smelled like mouse leavings. I turned it off immediately.
When I got home, I took off the blower, and it was completely packed with carpet padding, and so was the housing. No sign of a mouse...this time. I also removed the fan resistor, and it had stuff in it too...lucky I didn't burn up!
I shop vac'd the ducts out, removed the heater core cover, and sprayed everything I could get to with Lysol, then I decided to poke around and see where all the ducts go, and what those flappers do. I discovered that when it is set to max a/c, a flap opens up directly to the blower, and it is free to suck up all the crud it wants.
So, I have two questions: One, has anyone ever fabricated a cabin air filter or at least a screen to go over that opening, and two, where is the return air duct located, i.e. where does the air go back to the blower when not set to vent?
When set for MAX A/C, the system recirculates air from inside the passenger compartment. That's the flap that you see opening up above the passengers feet. This is the only heater control position that pulls air in from the interior and recirculates it. In all other position settings air is pulled in from the cowl screen at the base of the windshield.
So when in MAX A/C, the air is pulled in at the passengers feet and pushed out the vents in the dash.
In all other positions (other than MAX A/C), air is pulled in at the base of the windshield, comes out whatever exit(s) you have selected, and then eventually finds it's way out of the interior via the one way duct vent thingies in the pillars at the rear of the doors. One per side.
When set for MAX A/C, the system recirculates air from inside the passenger compartment. That's the flap that you see opening up above the passengers feet. This is the only heater control position that pulls air in from the interior and recirculates it. In all other position settings air is pulled in from the cowl screen at the base of the windshield.
So when in MAX A/C, the air is pulled in at the passengers feet and pushed out the vents in the dash.
In all other positions (other than MAX A/C), air is pulled in at the base of the windshield, comes out whatever exit(s) you have selected, and then eventually finds it's way out of the interior via the one way duct vent thingies in the pillars at the rear of the doors. One per side.