What causes the headlights to surge bright for a second or two as well as a brief alternator light to go on on a 94 CavalierVoltage regulator going bad Alt and battery have been tested?

sounds like the alternator is going bad to me. ive had a car before that it started going bad twice... got rid of that old hunk of junk and got me another one. but try replacing your alternator. is not that expensive, usually 60 bucks.