03 1500 Rebuilt 4.7 after spinning a bearing. After install ,I'm getting power to relay. But fuel pump won't turn on. I can jump across the relay and my fuel pump will run. Now if I pull the jumper after pressure up truck will start and run for a few seconds but then dies of course. If I leave the jumper in truck won't start. Pull the jumper start truck replace relay truck will die instantly. I'm guessing I'm not getting a ground signal from the ecm. Anyone have any ideas where to start to try and figure this out? It's kicking my ***.

 

You should see 12 volts on pin 30 regardless of key position. 12 volts on pin 86 with ignition in start, or run. PCM controls the ground side (pin 85). Are you jumping 86 to 85?? (and the pump should run constantly, so long as the key is on.)