No power to fuel pump

[hachigo87]

I recently just bought an 85 GT-S coupe under the assumption that it had no compression and needed an engine swap. Build thread link:
viewtopic.php?f=7&t=2353&p=10680#p10680

Anyhow, after flipping the exhaust cam and retiming it I did a compression check just on cyl 1 so far that yielded 175, a lot different than 0! My issue now is I can't hear the fuel pump run. I've checked most of the fuses, particularly the EFI and Engine fuses, all which look good. The fuel level sender has power and the gauge works, however when checked with a multimeter the pump has no power.

We've run power straight from the battery and stolen a ground from the taillights and still no pump. I'm not putting it past this car to having a bad pump and wiring, but it seems odd. So far I've already ordered a replacement pump just incase but I'm crossing my fingers here that someone might have some insight as to something I may have overlooked.

[Jehuty77]

If your giving it 12v and a proper ground and it still doesnt work, then its toast.

If you have a diagnostic port(I think only kouki models had it) you could jump B+ and FP to force on the fuel pump.

[hachigo87]

If your giving it 12v and a proper ground and it still doesnt work, then its toast.

If you have a diagnostic port(I think only kouki models had it) you could jump B+ and FP to force on the fuel pump.

I'm wondering if stealing a ground from the tails was enough? Unfortunately its a zenki so no such luck there

[ga_goosh]

if you think the pump is good (even after directly jumping it) then you should check your afm by opening the flap. if the pump still doesnt come on then check the circuit open relay. you can jump the relay and it will cause the pump to continuously run. also with normal operation the fuel pump only turns on during cranking. to tell you the truth if you applied 12v directly to the pump and it still doesnt work then i would point to the pump.

[Jehuty77]

Ground it the same place the stock harness grounds the fuel pump, theres a bolt where a bunch of grounds are along the rear panel(i think near where the liscene plates bolt from inside the hatch. you'll see it clearly, i believe their doubled up white wires. sand sound the bolt and the metal, get a good ground.

[hachigo87]

Thanks for the feedback so far. Later today when I get home I'm going to try keeping the flapper door on the AFM open, bypassing the relay and checking for power so I can rule out wiring or relay and worst case I'll try regrounding and giving power directly to the pump with some nicer, better gauge wire.

I'll keep you guys posted, thanks for all the feedback so far, keep it coming!

[Jehuty77]

Before you mess around with the AFM and such, just run 12v and a good ground to the fuel pump, if it doesnt come on there is no point doing the other tests, until the fuel pump turns on with 12v and a ground, there is no way it will turn on via any other method.

The AFM can send a signal to cut off the fuel pump(i forget how/why) however if your running 12v and a ground directly to the fuel pump, you have by-passed any fuel pump cut off.

When my friend had this issue he used female blade terminals spliced with some wire to run the connections(one to ground and one to a 12v source), the female blade terminals plugged right into the fuel pump plug. Its not correct, but for testing it will get the job done.

I re-read your first post, did you compression test all 4 cylinders? if not, do that too.

[builtnotbought]

have you check if your fuel relay is still good?
it's located in the passenger kick. it's black and yellow