Fuel pump won't prime

MadwickMadwick New Wagonist
in Engine & Drivetrain
US 90 civic wagon dx d15b1 automatic fwd urban brown

i cant figure out why the fuel pump will not prime when the car turns on. i tried running a 12v wire staright to the pump and it primes. pump works and from what i can see, the wires are in operating condition. besides the main realy, which has been changed, what could cause this? ecu? another relay?

any help will be welcomed.

thank you in advance.

Comments

  • CharbCharb Administrator
    How long ago was the relay replaced? Was it replaced with a new or used one?
  • hellmeromahellmeroma Banned
    have you checked your fuse?
  • 503Wagon503Wagon moderator
    I'd check the main relay first, I'm not sure if the pump is on a fuse, or which one it's on, I'd have to check my book at home....is anything else not working or just fuel pump prime problem?
  • JDMWago666JDMWago666 Senior Wagonist
    The main relay runs off the same fuse as the alternator. #14 I believe.
    EDIT: The fuel pump runs off #14 fuse, not sure about the main relay.
  • NZ-DB8RNZ-DB8R Moderator
    Relays die frequently enough, especially if it was second hand to start with. The contacts wear then begin to arc with each open/close action and can eventually fail.

    Check you have voltage at the pump when you turn the key and go from there
  • PeterPansWagovanPeterPansWagovan Wagonist
    Ignition switch IMHO, good luck bud
  • MadwickMadwick New Wagonist
    main relays are old. they both make clicking sounds when the ignition is in the on position. before i was able to use a constant 12v to the pump to check its functionality and now it wont even prime when i shock it with 12v.

    sorry it took so long to respond. thank you for responding as you did.

    the clock for some reason isnt working either.
  • MadwickMadwick New Wagonist
    the only light that comes on is the battery light. im not sure which other lights should show but im not sure whats wrong.
  • JDMWago666JDMWago666 Senior Wagonist
    Battery light is the dummy light for your charging system.
  • MadwickMadwick New Wagonist
    thats what i mean. its the only dummy light that comes on. no others.
  • JDMWago666JDMWago666 Senior Wagonist
    Check all your grounds, relays, all your fuses(get a tester and check on both sides of the fuses, there should be a little piece of metal on each side exposed) Other than this I can't really think of much else. Relays go out rather quick so I'd go for that first than check all other areas. Alternator going out could be the problem with your dummy light but don't qoute me on that one.
  • JakerJaker familEE
    What prompted the failure? Did you do some work on the car, or did it just start messing up out of the blue?
  • MadwickMadwick New Wagonist
    hey guys flow me to my personal thread. i temporarily fixed my wagon. hopefully ill see you over there to help resolve my other issues.

    thanks chadwick

    viewtopic.php?f=5&t=7134
  • JakerJaker familEE
    So you changed the engine harness. Make sure you've connected the engine harness ground at the thermostat housing. This is the ECU ground, and since the ECU controls the main relay and the fuel pump, this is more than likely the issue. I posted a reply here as well as your member's ride thread, as this is a more appropriate place for this information. Hence the reason you posted your initial question here.
  • MadwickMadwick New Wagonist
    well i do still have the issue with the fuel pump but i didnt want to have a new thread for each of my issues with the car(tps, vacuum lines, rear wiper, radio harness, brakes) thanks for your help and advice.
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