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  • avatar 0patience 05/05/09 11:46 pm PST

    You didn't indicate the year, but I will assume it is a late 90's F series.

    If you tap on the relay, will it activate?
    Check up under the dash, by where the brake pedal would touch the firewall and there is an inertia switch (roll over switch). On the top, is a button. Check to see that it is pressed in.

    It's also possible that the fuel pump relay is the problem too.

Answers

  • 0patience 05/05/09 11:46 pm PST

    You didn't indicate the year, but I will assume it is a late 90's F series.

    If you tap on the relay, will it activate?
    Check up under the dash, by where the brake pedal would touch the firewall and there is an inertia switch (roll over switch). On the top, is a button. Check to see that it is pressed in.

    It's also possible that the fuel pump relay is the problem too.

  • bronco71 05/06/09 11:27 am PST

    sorry about not including more info about my truck. It is an 93 f-150 5.0 L engine 4x4 automatic transmission with overdrive.

    I was told that by grounding the #6 pin on the data link connector and the fuel relay pulls in and the fuel pump turns on and pressure builds, that that whole circuit is good. i.e. relay, pump, and selector switch.

    BRONCO 71

  • 0patience 05/07/09 9:39 pm PST

    It sounds like the inertia switch is probably the problem, so check it first.
    If you can push the button on the top down, then it tripped.
    Make sure the button is down and then check to see if it will start.

    If it doesn't start, put a fuel pressure guage on it and see what the fuel pressure is.
    (Harbor freight sells a cheap pressure tester for about $15.00
    Fuel pressure should be;
    engine off 35-45 psi
    engine running 30-40 psi

    If it shows fuel pressure then you will need to use a spark checker/tester and see if it is getting spark to the plugs, if it is, then check the compression.

    Oh, after re-reading your first post, I should clarify, the fuel pump relay will kick off, once the system sees fuel pressure and will activate again, when the engine is cranked.

    Let us know what the fuel pressure is, if it shows spark and what the compression is and we can go from there.

  • max1105 09/21/10 5:38 pm PST

    i have a 1994 ford f150. sometime it will start right up, other times it will just act like it is not getting any fire at all. i have replaced plugs, wires, brain, coil wire, and distributor. i was told it may be in the fuel pump.

  • bigboychukk 03/30/11 8:48 pm PST

    I have a 94 thats doing the same exact thing. although, i've gotten the spark back my fuel injectors are still not spraying. To get my spark back i simply regrounded the throttle body on the left side back to the negative post on the battery.Then regrounded the battery back to the body again both with the heavy duty battery cable you can find in a auto store.

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