89 Cutlas Ciera

89 Cutlas fires right off, runs about 3-6 seconds and dies, will start right
back up, but then dies in same amount of time. It has a 2.8 V-6, auto. Fuel
preasure is 40-42lbs running and just prior to start. It appears that
something is shutting the injectors down, because it has spark untill it
stops spinning when it dies. New TPS and Oil preasure sensor. Could it be
the Crank position sensor, would it "start" - even though faulty, or
possibly the crankshaft position sensor, (not sure it has one)? What would
cause the computer to shut down the injectors?