mcpaddleboat

Hey everyone I'll get right to it. Truck ran fine but the battery was replaced backwards and shorted out the fuseable link going to the alternator. I replace link and am now getting no fuel. I am not getting any power on the green/white control wire at the fuel pump relay,but am getting power on the orange wire from fuseable link. Could this be a ignition control module failure? Or is this an ecm problem? Truck runs when you pour gas in it. fuel pump pumps when bypassed at oil pressure sensor, but won't pump fuel at injectors. Checked every fuse I can find but still nothing.
​​​​Thanks

Gumby22

What engine? Does it have dual tanks?

mcpaddleboat

5.7 350. No just single tank

Rednucleus

For my 93, when ICM goes bad (on my 3rd one) it runs if I add fuel to throttle body, but injectors don't fire. Easy change and not that expensive a part; give it a try.

mcpaddleboat

Thanks I'll try that and let you guys know

Gumby22

You said you weren’t getting power on the dark green/white wire at the fuel pump relay - when were you checking for it? At key on, the ECM will energize the relay for a few seconds in order to prime the fuel lines, but then it cuts power to the relay until cranking begins. If you were checking for power with the key on but after a few seconds had passed, the ECM may have just de-energized the relay as it’s supposed to.

The black/white wire is the ground circuit for the coil side of the relay. Remove the fuel pump relay and jumper a test light between the dark green/white and black/white wires. Have a helper turn the key on or Rig the light in a position where you can watch it as you turn the key on. If it lights for a few seconds then goes out, the control circuit for the relay is in tact. If it doesn’t light, try grounding the test light to the engine block or direct to battery negative and repeat the test. If it still doesn’t light, repeat the test at the ECM by back probing cavity A1 - if it lights, there’s an open on the dark green/white wire between the ECM and the fuel pump relay. If it doesn’t light, the ECM may be damaged, but you’ll have to verify power and ground feeds to the ECM first.