My 87 gt has been squealing at first start in
the morning for a second,but then stops.Now with the days getting shorter,I been having to use my headlights in the mornings.When I turn my lights on,the squealing gets worse,if I give it gas ,it will get even worse.However it will stops as soon as the engine gets warmed up.I do also have problems with the car staring ,when the engine is hot.I don't know if this helps,but on some days ,I can hear a humming noise from the engine,seems to be coming from the passinger site.I hope some one can help on finding the problem.

Sounds like the alternator belt is bit loose or worn out. Tighten it a bit, and if that does not help, replace it with a good "premium" quality belt like Gates or Goodyear. Fieros do not like "cheap" belts.

Mike

DEFINETLY, a belt. Probably the altenator because you said you hear it when you turn on the headlights which makes the altentor work hard for a second. Its always good to change belts becuse if one breaks you could be stranded. Like mwbackus said always use high quality belts they are way worth the extra 2 or 3 dollars. They last a long time and dont squeal easy.