Trying to get an old 1992 S-10 Blazer, 4.3 V6, started. Issue: fuel pump does not pump with ignition on. I removed pump to check, I hot wired the pump (grey testing wire) and it pumps fine. I also replaced the ecmb fuse, fuel pump relay and the oil sending unit. I don't know where to attack next. Any advise?

 

Ignition switch would be my next thing.

 

do these have the little 3" red wire on the fuel pump relay? i know you said you tested the fuel pump by hot wiring it, but the little red wire would help determine if theres a poor or broken connection between the relay and pump

 

No red wires to relay. Relay has 4 wires; orange, grey, black/white stripe, green/white stripe. I will be checking the wires today. Wiring diagram shows that the orange wire comes from the ECBM fuse and should be hot when entering both fp relay and the oil pressure switch. Grey wire feeds the fuel pump completing the connection with orange wire inside the fp relay. Black/white is a ground wire and the green/white is a fp relay control. I'll be focusing on the orange to start.

Update: Wires checked out good. I cleaned the grounds on a few of the wires, gave it some quick start, and a jump and it started & kept running and starting. Now it is time to move to the engine.