Quote Originally Posted by NomakeWan View Post
The system description can also be found in the FSM. For my vehicles, it's "Chart A-5." Your vehicle may vary. However, the way GM laid these out was pretty much identical from car to car in the late 80s and early 90s, and it's exactly as Six_Shooter described above:

charta5.jpg

The important part here being, "It will remain "ON" as long as the PCM is receiving low resolution reference pulses from the distributor ignition system." That's because on my cars there's both a low and high resolution pulse for the distributor, but on your vehicles there's just the one distributor pulse. Either way, as long as your ECM is receiving that distributor signal, it will attempt to energize the fuel pump relay.
Thanks! That's what I was looking for.