I have a 1987 pontiac Fiero gt and it turns on for a minute then shuts off, after a while it turns on again and then it shuts off. I've already replaced the computer, fuel pump, and full tune up.
Take it to a reputable auto repair shop (preferably one that is familiar with Fiero problems and they are hard to find). You might could have saved yourself a good bit of money replacing things that weren't necessary.
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