91 3.1 No start

[size 12]

Hi I was hoping to get a few opinions about why I can't solve my 1991 lumina no start.

Got in my car at work at lunchtime , the car was on empty and I was going to the gas station, I no more got going and the car stalled so I figured I was out of gas, restarted the car and drove to the gas station. Left the car running while I pumped gas. Then drove a mile and ate lunch. Finished eating and started the car and went about two blocks and it stalled again. Never did restart.
I checked every fuse in the car.
TP Sensor is good, ECT Sensor is good, maf sensor is good , map sensor is good.
I checked the fuel psi at the rail and it was 45psi while cranking and 42 psi with the key on. I checked the spark and I thought it looked weak but it was outdoors and very bright . I meant to check the crank rpms on the scan tool but accidentally checked eng rpm by mistake, which was 0 because the car didn't run. So I checked power and ground to the ignition module, then I checked the resistance of the crank sensor which was good. I replaced the ignition module , then I replaced the crank sensor, then I replaced the crank sensor to ign. module harness , then I realized I was looking at eng. rpm instead of crank rpms. I also regapped all the plugs(which were dry) and replaced the rear three plug wires just because I happened to have brand new ones.

Starting over I now checked the injector ground circuit terminal and the injector low reference circuit terminal at the ecm side of the black mini harness connector located under the ecm with a test light connected to batt + while cranking. The test light should blink when cranking on both terminals, it was 'steady on' when checking one of them.
That meant that it was either a bad ecm of a bad injector or a bad injector wire. The junkyard had an ecm for cheap so I tried it. No Luck.
So now I'll have to pull the upper intake plenum to get access to the fuel injectors and the wires, there is no separate injector harness connector on this one.

ANY THOUGHTS ?

[Airjer_]

Don't these have the batter cable that runs over the the little fuse block on the drivers side? I think the jump start + post is there. Make sure that connection is tight and clean between the cable and the fuse block.

[Bearwulf]

Try unplugging the 6 post harness from the ICM see if engine will start. Junkyard ecm? Tsk tsk tsk, even they don't know if the part is any good.