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1994 f250...where is the fuel pump relay?

Discussion in 'Ford Trucks' started by cgillispn, Oct 22, 2004.

  1. cgillispn

    cgillispn Member
    Messages: 38

    Is there a fuel pump relay for this truck? It has dual tanks, are there two relays? If so, where is are they (it)? Thanks, Craig
  2. b2driver

    b2driver Member
    from MD
    Messages: 89

    There should only be one fuel pump relay. Look for a power distribution box under the hood, it should be in there.
  3. streetsurfin'

    streetsurfin' Senior Member
    Messages: 770

    Just curious what your problem with the truck is. No fuel at all or problems when you try and switch tanks.
  4. cgillispn

    cgillispn Member
    Messages: 38

    When i switch to the front tank, the fuel pump doesnt kick on and the fuel guage goes as far full as teh needle can go. I put in a new switch and the fuel guage worked for a couple minutes but, the fuel pump didnt work. I switched back and forth a couple of times and then it stopped working all together (front guage and pump, right back to square one).
  5. cgillispn

    cgillispn Member
    Messages: 38

    I messed around with it today. i dont know if its worth it. the guage is working again (on empty). so its either the relay or the pump. however i pulled the pump out and the tank is bone dry so it is all rust flakes floating around in there so, i dont know if its worth the money to get the front tank in service. the rear one is the biggest so thats what matters most
  6. naco

    naco Member
    Messages: 49

    there is a fuel cutoff switch located in either drivers or passangers side kick panel
  7. cgillispn

    cgillispn Member
    Messages: 38

    naco, what does the cutoff switch look like? also, is there just a reset button on it?
  8. streetsurfin'

    streetsurfin' Senior Member
    Messages: 770

    This goes back to about an 88(+/-) truck that I borrowed from a friend once. His wouldn't pump enough fuel at highway speeds to keep it running. It would sputter at 60 and run better as you pulled off the highway or stopped to look at it. I reported it to him and he had it fixed. He'd known of the problem but just didn't use the extra tank. I wasn't innvolved in the repair but from what he told me, I thought there was a switching valve that was clogged from the tank debris (bad gas from non use of the tank over time), and wouldn't switch completely to the second tank. Not the relays but a valve in the fuel line that would plumb the two fuel lines into the one line that fed the fuel injection. I'd look into a shop manual and see if there isn't such a part.
    Last edited: Oct 25, 2004
  9. 85F150

    85F150 Senior Member
    Messages: 340

    Dont worry about the fuel cutoff switch or inertia switch as it is called it completely cuts the fuel system off. Your problem is a harder to solve without being there. So here is a little help.

    if the truck still runs with the front tank empty and and the switch is on the front it is in the fuel selector valve. It is mounted by the t-case on the frame. HAs 4 or so lines going in then 2 out IIRC.

    If you are havin probs with one pump not coming on but the other does and have replaced the switch, the problem is usually the pump or in the harness going to the pump. Go to the pump that isn't working and check the wires with a test light, IIRC at least one should light up when the key is turned on. Most common problems i have run into our bad grounds. My 88 has a bad selector valve but the front sending unit jumps between totally empty and working correctly. i am just too cheep to replace it :D

    i would do the test light trick on the working tank first so you know which wires do what. Then if you aren't getting one to light up the same as the other tank run a positive wire from the battery (just a temp thing) to the wire that should be lighting up on the non-functional tank. And if that solves the prob you know you hve a bad power wire somewhere. I would start at the tank and work my way back through the fuel harness though. good luck