Most likely a bad idle air control valve. When checking and replacing it spray the throttle body out with some throttle body cleaner.
your car is idleing to high you need to have that looked at your car is idleing to high you need to have that looked at
The throttle cable runs on the backside of the the intake manifold. There should be 2 10mm screws. Loosen them with the car idleing and let the accelerator slowly close until your at the desired idle.
1 300 rpm
Check the EGR valve.
look for a loose vacuum line.
Probably have a misfire or lean fuel mix NELSON
Needs a recharge
check the idle control valve not that hard to replace and inexpensive
Look and listen for a vacumn leak under the hood.
You probably have a cracked EGR tube The Fiero Store has replacements Google them
air in the lines, bad fuel, dirty air filter, need more info to properly troubleshoot
check the overload relay part # 201.540.32.45