1991 cutless cruiser

3.3 eng will run 3 seconds then stall,new fuel pump,computer,crank sensor. shuts down injectors,but still has spark while cranking

Im thinking the oil pressure switch is bad. On these cars, when you crank the engine, the fuel pump relay gives power to the fuel pump. Then once it starts, the oil pressure switch takes over, and if it senses a loss of oil pressure, it shuts off the fuel pump. If the oil pressure switch is bad, it could be telling the computer that there is no oil pressure and to shut off the fuel pump. Amount of gas from when the fuel pump relay primes it lets it run about 3 seconds.

I checked oil psi switch the injectors shut down after 3 seconds I dont have any anti theft devices coolant switch checked out ok too