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RobbieSS
04-02-2020, 05:05 PM
So i purchased a 95 240sX se with a blacktop sr swap in it. It has a wiring specialties harness installed in it but im confident that the previous owner installed it wrong. At first it would crank but not start. I narrowed it down to the fuel pump and I replaced it, I also relocated the battery to the trunk. The car started up and I took it for a drive and it died halfway through. Realised I had no fuel so I filled it up and It wouldn't start back up. Now the car doesn't want to crank and there isnt a fuel pump prime. I used a volt meter to apply 12v to the pump and nothing. Any help would be greatly appreciated.
Side note: I have checked fuses and a couple grounds and everything looks in order. Also the fuel pump relay

FaLKoN240
04-02-2020, 06:52 PM
My friend was telling me that the OEM wiring in Nissans isn't sufficient and should be upgraded/hardwired with its own relay. When I have more info and get this done on my own car I'd be happy to share.

RobbieSS
04-02-2020, 07:39 PM
Oh sweet, thankyou man keep me posted if you find anything

coupesallday!
04-03-2020, 01:04 AM
On the harness there should be a long positive wire going to the fuel pump positive terminal, at least that’s what wiring specialties says. I haven’t done it myself yet but here’s the link
https://drive.google.com/file/d/0B9F33_M_GgENMUNrRklETWZzOUk/view

brndck
04-03-2020, 08:18 AM
when you say "the car doesn't want to crank", you need to sort that bit out first before worrying about fuel delivery.

THEN, if you give 12v (and the ground is good) to the fuel pump, and nothing happens, that pump is no good.

once you get the car to crank, and verify that you have spark, see if the car will start on starter fluid.

RobbieSS
04-03-2020, 08:27 AM
Update: So I was grubbing around the internet all last night looking for an answer and I saw something that sad jump pins 3 and 5 on the fuel pump relay. So I did and the fuel pump kicked in and I was like woah, I had a brand new fuel pump relay so i plugged it in but it didn't work. What does this mean is my ecu bad?

brndck
04-03-2020, 09:37 AM
Update: So I was grubbing around the internet all last night looking for an answer and I saw something that sad jump pins 3 and 5 on the fuel pump relay. So I did and the fuel pump kicked in and I was like woah, I had a brand new fuel pump relay so i plugged it in but it didn't work. What does this mean is my ecu bad?

sooooooooo you need to get the FSM and look up that relay, find what triggers it. . . . and go look there.

I cant remember off the top of my head if its a ecu signal or just the ignition switch that commands it.

collegekid
04-03-2020, 11:16 AM
Wow absolute shitshow in here. OP, you need to calm a tit, stop running around doing dumb shit, and start over. Don't sit here and throw parts on the car.

You have a S14 with S13 Sr20 swap. Which wiring harness exactly do you have in the car? Is it a proper S13Sr into S14 specific harness or did the previous owner adapt whatever wiring specialties harness he could to your car?
Why do you say he installed it wrong?

Also, there have been changed made to the WS harnesses, see their site for their harness install guides (they say changes have been made around January of 2020)

Don't look at generic wiring harness diagrams, look at the one specific to your car. every connection should be secure.

Provide details as to how exactly you relocated the battery to the trunk.

Step 1: Answer questions.
You need to identify what exact harness you have.
Use your multimeter and verify stuff that has to have power, per the diagrams in the FSM/WS diagrams.
Car should crank with or without fuel, so check the starting circuit.