Thanks to all for the advice on where mice can get into the HVAC system and then into the cabin. Here is a diagram I made based on the the GM diagram of the Fiero HVAC system. I didn't show the two door motors or their contact patterns because the door diagram is enough to show where mice can get in and nest. I am going to remove the wiper Cowell this week, clean out the nest that is there, remove the fan and resistive feedback coil, clean out anything I can find from there inward, then put 1/4 inch galvanized steel mesh over the outside air port (inlet) and over the two wiper tray drain tubes where they drain out under the car. I will post photos later.
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Paul Romsky
[This message has been edited by Romsk (edited 12-01-2022).]
