1989 240gl in tank fuel pump

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Hey guys,

I have a little dilema that I hope you can confirm for me.
The engine started to slightly miss at freeway speed,just once in awhile.then started to run rough until it would'nt start. I found that the f/p relay was acting up so I changed it with one of my spares. It now clicks with KOEO and the other click in the start position. With key in on position I'm not hearing lift pump running so I did the jumper routine between #4-#6 fuses for the main and the in tank pump and they both work. Did a fuel pressure test and got 40psi,ccrimped the return and jumped to 100psi. Assuming main pump and pressure regulator was ok(also no fuel in vac. line) I pulled the lift pump from tank. Bench tested with a short 12v blast and it ran. Check voltage at the harness and was getting 10.2 volts. I can understand a lower voltage for the sender and I think that it would be enough to run the pump a little slower. Ok, 10.2 volts at the harness and measured voltage at + - terminals on the pump with a drop to 1.2volts.
I'm not one to just throw parts on to see if it fixes the problem but it sounds to me the pump is shot or am I supposed to be getting at least 12 volts at the harness and do some wire tracing?

Thanks for your time
Joe B