Paulc19

So im extremely close to finishing my turbo II swap. The one thing that isn't cooperating with me now is the fuel pump. I swapped out the NA fuel pump for a OE turbo II fuel pump. We got it wired and connected, but when you go to turn the key into the "on" position (which should prime the fuel pump), nothing happens. No fuel pressure, no click signifying its turned on, nothing. The motor cranks, and from what my friend said, the wires going to the fuel pump is feeding electricity. So what could be my problem?

j9fd3s

iTrader: (3)

nothing, the fuel pump does not prime on a Mazda. the fuel pump runs when the key is in the "start" position or when the ECU sees an Rpm signal and turns it on.

Paulc19

well i turned the key to the on position and im not getting any fuel pressure in any of the lines. any idea why? before i started the swap whenever id turn the key to the on position you would hear a click of some kind signifying that the pump turned on and is fueling the injectors.
right now the injectors arent getting any fuel. it will crank, but because there's no fuel being sent to the injectors it wont start.

NCross

iTrader: (18)

Pull the pump and inspect the wiring. Check for voltage while trying to start the engine.

Paulc19

from what my friend was saying, the voltage was good. We haven't done anything with the wiring and the old pump worked perfectly. ill check the wiring, though.

j9fd3s

iTrader: (3)

the pump should run when you have the key to start, if you just turn it to on, you will get nothing, unless there is an RPM signal to the computer.

there is also a fuel pump jumper, its a yellow 2 pin connector on the right shock tower, put a jumper in that and the fuel pump will run with the key in the ON position. if you use the fuel pump test connector and the fuel pump does not run, there is something wrong.

Paulc19

It was in the position right before you start cranking the motor. Start, on, which ever, it was in that position. The fuel lines going to the injectors had no pressure.

docbong85

Did you jump the yellow connector by air filter box/strut tower?
Does your car have a fuel cut-off switch?
Have you tested the relay as per the FSM?

NCross

iTrader: (18)

Engine fuse blown?

docbong85

I figured it out. It was the fuel cut-off switch I replaced wasn't rated high enough, and it burned when I depressurized to attach fuel pressure gauge.

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