When I start up my 1994 firebird formula 350 lt1 it bucks every so often on a cold start then when I drive it every once and a while. What could be the problem? I replased the fuel injectors, fuel rail, and did a tune up. The guy I bought it off of said it needed a new fuel pump cause the amps were to low. Please help I really dont wanna sell it, its my baby. Pleaase help!