GMC Repair: 87 gmc 1500 fuel/electrical, throttle body injection, fuel pump relay

Question
i just bought a 1987 gmc 1500 its got the 350 motor with throttle body injection. it does not run because the fuel pump is not getting power. the fuel pump is good the fuel pump relay is good however i noticed that it does not always click when the key is turned. i traced/tested the wires going to the relay and found that the green/white wire coming from the ECM is not always getting the 12v signal it needs to engage the relay. i also noticed the service engine soon light is on. im hoping it might be an ignition signal problem and not a bad ECM, so any suggestions on where to go from here would be great.

Answer
Hi
The ECM looks for the ignition signal wire from the Distributor, specifically the Dist Ignition Module under the cap.
I would check it first. Does the truck fire?
If not check the whole distributor assy.
Hope it helps.
If need more help please let me know
PAul