by 85 SE VIN 9 on Mon Dec 28, 2009 10:01 pm
Your headlight gears are stripping. Download the PDF from the Michigan Fiero Club. You can find it in the Firero Online Service Guide.
There are numerous gear replacement options, but almost all require considerable time, effort, and some tools you might not have. You have to remove and break open the headlight motor and clean out the pieces of rubber that used to connect the motor to the gear. You have time though. One of my headlights was stuck up with the motor running whenever the headlights were on - six months ago - and still is. I got a gear and motor rebuild kit from the Fiero Store for about fifteen dollars.
Google something like 'Fiero headlight rebuild' and you'll find some Utube videos on how to do the whole process. The headlight system is very similar to the Firebird system. There is a good pictorial on that process.
Since your headlights are actually still working you might be able to reuse the gear by just turning it around. Apparently it only uses half the gear, so if you turn it around so it uses the good part it will still work. You'll still need the rebuild kit without the gear, about seven dollars at the Fiero Store.
One neat trick from the Michigan Fiero Club PDF allows you to disable the headlight motors so they don't go down every time you turn off the lights. I got a push pull switch, pushed the dimmer control out of the way, cut the white wire from the headlight switch, attached the ends to the switch, and mounted it in the dimmer wheel slot. With the switch in the headlights don't go down. Pull it out, they close. I was hoping this would stop the running motor, but no such luck. The Michigan Fiero Club PDF says if you disconnect the blue connector at the headlight it will stop the motor. Maybe that's just when the headlight switch is off, because the motor still runs when the lights are on.
With that in mind I have this suggestion. Before working on these motors or the headlights in any way - disconnect the battery. KEEP YOUR FINGERS OUT OF THE HEADLIGHT SYSTEM ANYTIME THE BATTERY IS CONNECTED. THERE IS NO WAY TO BE CERTAIN IT WON'T START RUNNING!