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5.4 Ford fuel rail sensor and engine spark trouble shooting

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  • 5.4 Ford fuel rail sensor and engine spark trouble shooting

    So we are able to buy early 2001-03 vintage Ford F150s coming out of the Bay Area cheap but we are seeing new issues beyond fuel rail sensor failures. One truck does not deliver fuel even after good sensor change. What's the next step? Computers are available, I saw one post about two computers - a fuel computer and a main CPU, does not sound right to me. Truck cranks and runs on starting fluid, tanks are full, no fuel delivery.

  • #2
    Are you getting fuel to the injectors on the fuel rail? If so , what is the pressure ? If you have proper fuel at the rail, and the injectors are not firing, ? CNG injector driver module ? ( the so called second computer) .

    If no fuel to the rail , work backwards , any cutoff valves, fuel pressure regulator, Tank solenoid valve ( be vary careful) . If you have twin tanks, the chance of both tank solenoid valves being bad is near zero.

    These vehicles should have a re-settable impact sensor , same as a gasoline vehicle that will cut off fuel.


    • #3
      I have a 2006 F150 with 5.4 that had the same no start issue except with the start fluid.
      There is a block that primes the fuel pump for a second when the key is turned and switches to power the fuel pump when the engine starts. It is located above the rear axle on a frame member. The aluminum housing against the frame member rotted out on mine. The new one has spacers to keep it off the frame. Must have been an issue with differing metals contact.
      Just my experience... Yours may be dedicated and that is a different story.