93 astro van 4.3 tbi injectors lose ground signal

[mrutah12]

Good day
I have a 93 4.3 engine and trans out of a 93 astro van that my buddy put in his 53 Chevy pickup got it wired up used the engine harness that came with the motor its using ecm #16168625 tired starting the injectors would not squirt fuel so I took the icm out and had it tested it tested bad put the new one in and still no fuel coming out of the injectors have fuel pressure spark it will run if i squirt fuel down it .so I did some more research and I saw an article about that they are not pulsing so i bought a noid light no pulse. So here is the weird thing if I turn the key and ground the Injectors and it will spray then I start the truck it will run on its own and the injectors work but if I shut it off it will not start back up unless I ground the injector then I can start the cycle all over again I've checked my grounds the black/white wires they look good also We don't have a fuel pump relay in the system the fuel pump is wired to come on with the key at this point I still believe it is a ground problem but were Should I put the fuel pump relay back in the system could the ecm be bad or am I missing a ground wire somewhere Please help I don't know where to look next

[dave w]

The computer controls the injectors with ground pluses. The faster or the more frequent the ground pulses that are sent from the computer to the injectors, will cause the injectors to spray fuel.

I would NEVER operate a fuel injection system without a fuel pump relay! I STRONGLY recommend using a fuel pump relay wired EXACTLY like the factory schematic!!!! Your computer might not be getting a "Fuel Pump ON Signal" without a fuel pump relay being wired like the factory schematic.

If there is a still a problem with the injectors not spraying fuel, after installing a fuel pump relay, then try a different computer.

dave w