fuel pump test question
 

i need to test my fuel pump and want to give it voltage directly, but without taking it out yet, anyone know the leads on the fuel pump plug that I need to give voltage to?

the manual lables the leads a,b,c,d...with a,b, on the bottom, and c,d on the top...d above a and c above b

so like this if you are looking in the plug...

d - c
a - b


This is the plug on the tank, not going to the tank.

according to what i just saw in teh woring diag, its a and c that i want to give voltage to, sound right?

Fuel pump pos is red/white, and negative is black.

The green? and little blue wires are for the fuel level sensor.

thanks cavellm, i read your thread about your pump going south... did you get it all fixed up?

https://www.rx7club.com/forum/showth...5&pagenumber=2

why not use the diagnostic box?

Unfortunately not. It ran last night after unplugging and plugging back in the connector on the bottom side of the tank cover. Unflooded it and boom, ran for 20 minutes. Started and stopped it twice more.

Changed my oil, then combusted a little but died a few seconds later.

This morning tried unflooding it with no success. Took out the pump yet again and found its not getting power again. I can trace the power to the bottom side harness on the cover, but not to the terminals. Fucked up thing is its the same on two different fuel pump assemblies. :(

i did use it for the first test, then i wanted to check the pump directly in case it was the harness/connectors.....

i found that the pump is gettin power an I hear it running....

.. but my fuel pressure gauge reads no pressure when the diag terminal is tapped to keep the pump on...

now im going to pull a hose and run the pump to see if its pushing any fuel anywhere...

tested pump, it flows just fine from what i could tell, jumped the FP at the diag terminal, turned key to on position, and the pump started flowing a pretty solid stream....

maybe the fuel pressure gauge dosnt read until the car is running?

decided to put it all back together since the pump was pushing fuel....

re-installed a plug I had out for testing, put pukmp connectors back and .... started right up ...

hehehe, these machines are an enigma

im guess a plug got loose and I re-attached it during testing...who knows....

Wish mine was an easy fix like that ;)

:-) yeah, good luck to you...

I am not a Mazda expert, but I am a fuel injection expert.
I didn't read the hole set of threads real close, however this is a fuel injected engine and the injectors must be pulsed by the engine computer. No pulse no fuel. Since you are getting spark this tells us the crank sensor is sending a signal up to the ignition system but since I don't know Mazda I can't say how the chain of events transpires. Most cars I have worked on will have spark even if the engine computer is unplugged, so this may not be a fuel pump issue. Normally the injectors are powered up and the engine computer grounds the circuit so connecting a test light in place of one of the injectors would tell you if a signal is being transfered.

/\ what ever you do do not put a test light anywhere near the fuel injectors. it is a bad idea even if it is a high impedence snap on one. use a noid. who wants to be the one guy whos ecu gets burned