91 GP Won't Run.

I have a 91 Grand Prix, 3.1L that won't run. It does have spark, but it appears that it is not getting fuel, and will run shortly if I give it a shot of ether. The fuel pump, the fuel pump relay, the fuse, the wiring to the pump, all check out good. We do get fuel pressure at the rail if we run power to the relay and the pump.... but it still will not start. We have swapped the computer and we do get a momentary pulse or signal at the fuel pump relay when turning on the key, but otherwise no voltage or signal when trying to start. We have also changed the crank sensor, and the ignition module.
Are there any other sensors or devices that the computer would be waiting on, or that are needed for the car to run? Any help would be greatly appreciated!
Thanks
Wayne

Check the oil pressure sending switch and wiring, the fp is routed thru that harness and switch.