Need help with fuel pump & oil pressure gauge

[Stripes]

I just got done with my swap and everything works except my fuel pump was not pushing anything at all. No power, nothing. So to make a long story short I figured out that there is a black and pink wire coming off the fuel pump relay which is a ground for the relay. I figured that wherever the wire was going was to another relay somewhere that completes the circuit when the key is turned to the "On" position. So to make sure this is what would make the pump work I cut the wire and grounded it, then turned the key and the fuel pump worked perfect. SO! At this point I am left with 2 options:

1. Bypass the wire by keeping it grounded, but doing this will make the fuel pump constantly working if the key is turned to acc, even if the car isn't running.

2. Figure out where the pink and black wire is going to and figure out what is causing that relay to stay open. I have done a bit of research and found that in many cars the fuel pump will not have a completed circuit unless the motor is getting a fuel pressure reading of some sort, which leads me to my next dilema.

If it is true that I have to have a fuel pressure reading in order for my fuel pump circuit to be completed, then my problem is that I may or may not have my oil pressure gauge installed correctly. I have an auto meter phantom gauge. The sending unit is properly installed, but I did not use the adapter to connect the stock unit as well. Also, I do not think my oil pressure gauge is hooked up right because I do not know what to wire the "I" pin to, and i'm guessing the "S" is what I'm supposed to hook the sending unit to. I checked the forum and there is nothing about how to do the wiring part and auto meter sent me instructions for a mechanical gauge but mine is electronic.... so efffffing lame.....

So here's a summary in case someone got lost in all that jibberish.

- I need to know if you have to have an oil pressure gauge and stock sending unit installed in order for the fuel pump to get power. If not, then what can I do to complete the circuit of the pink and black (ground) wire coming from the fuel pump relay without having it permanently grounded?

Please help. This is all I need in order to finish my swap. Thanks in advance,Matty

Oh and I don't think it will help but it's an s14 sr in a 93' hatch.
Modified by Touge' at 6:40 PM 10/5/2008

[Stripes]

never mind. Decided to install a switch

[Hijacker]

The black/pink wire is a ground complete to the ECU. The ECU grounds out the relay, and the relay provides power to the pump. So either your ECU isn't providing the ground complete, the wiring wasn't completed at the 2 plugs connecting the EFI and chassis harnesses by the battery, or you have a broken wire somewhere in the car.

As for fuel pressure, I have no clue where you heard that you need X pressure for the pump to run. The pump will run no matter what.

Also, fuel pressure does not equal oil pressure. Two totally different systems. Fuel pressure is derived from the FPR at the front of your fuel rail. The stock oil pressure sending unit only completes a circuit for a dummy light if pressure drops below a certain amount.

[Stripes]

I know that i did the wiring for the 2 plugs right (brown and gray) because everything else works fine, but how would the ecu provide a ground? I've got all my grounds hooked up... are you saying the ecu needs to be mounted to the chassis? That doesn't really make sense because then nothing would be grounded unless the ecu is

[Hijacker]

Power routing for that relay goes like this:

battery - > fuse -> relay coil -> chassis plug -> ecu -> ground

Most things on Nissans are ground completes. The ECU in this instance acts as a switch that completes a ground to turn the relay on. If you did the wiring for your plug properly, then you should check the exposed portions of the EFI harness to make sure the black/pink wire wasn't cut at some point, and make sure there is no corrosion on the pins at any of the plugs.

[Stripes]

I did all my own wiring, and i didn't touch that wire at all. That harness isn't even involved with a swap