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Fuel light on

Discussion in '6.9L IH & 7.3L IDI Diesels' started by I Bleed Blue, Aug 4, 2020.

  1. I Bleed Blue

    I Bleed Blue Registered User

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    94 7.4 turbo IDI. new to me truck. Been running good for a few weeks, fuel light came on so i changed the filter, light went out for a few days then came back. It had a new mechanical fuel pump but I went ahead and bought a facet electric fuel pump. Went to drive it today and same thing as before 3 gear hard acceleration and fuel filter light comes on. Where should I go looking for issues as I understand the light only come on if the ip goes into a vacuum and my feed pressure to the filter should be 9-11psi with the electric pump.
     
  2. chillman88

    chillman88 Supporting Member Supporting Member

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    Unfortunately that could possibly be your problem. People have been having mixed results with them lately.

    You need to check this out with a gauge. I went back to a mechanical pump for just this reason.
     
  3. I Bleed Blue

    I Bleed Blue Registered User

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    It’s literally a brand new electric pump and the mechanical one did the exact samething so I’m pretty sure it’s not the issue.
     
  4. chillman88

    chillman88 Supporting Member Supporting Member

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    It may not be, but I'm just saying don't rule it out as a possibility either. My pump was brand new as well not keeping up.

    I'd be looking for sources of air intrusion.

    Is your tank selector valve working properly?
     
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  5. I Bleed Blue

    I Bleed Blue Registered User

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    The selector valves switches tanks no problem. I don’t see any leaks so I don’t know if there’s air intrusion
     
  6. Fordman1920032003

    Fordman1920032003 Full Access Member

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    Definitely add a gauge. Classic diesel sells a nice feed line with a gauge. Also check your grounds and the condition of the plug on the filter housing.
     
  7. catbird7

    catbird7 Full Access Member

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    Recently had the same problem and I also started by replacing the fuel filter and considered replacing my 10 year old Holley Red pump when a friend suggested trying a quart bottle of Power Service Clear Diesel fuel & tank cleaner. The container tells you it makes 100 gallons however I dumped a full bottle in 1/4 tank of fuel, drove around for a few days on the other tank allowing it time slosh around in there then switch to the tank with cleaner while driving 3 miles to fill up. Gotta say, it seems to have worked, no more light! It's a little pricey but beats the heck out of new pump or pulling tanks. Good luck to ya!
     
  8. nhwrench01

    nhwrench01 Registered User

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    i had the same problem, but on a n/a. same setup, facet pump and a small filter before the pump. the fuel filter light would keep coming on. id change the spin on filter, and it would be good for a while. ... hear me out on this..
    I think removing the spin on would let the fuel in the line back flush the filter and push the crap back a ways. 3 or 4 spin on filters later, i knew there were other issues. i checked all the lines and fittings. Then i changed the small filter before the pump and cut it open...
    WOW, full of crud and who knows what. worked fine after that, untill i installed a turbo set up, the facet pump does not have enough flow for the increased fuel need of the turbo engine. the only change was adding a turbo, straight pipe and turning up the ip pump 2- 2.5 flats. ( was only at 1-1.5 flats before). i added a holley red and its been fine . get a fuel pressure guage and check it as you drive , my facet was at 3 psi. at idle and went to 1 psi driving... not good. Hope this helps.
     
  9. I Bleed Blue

    I Bleed Blue Registered User

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    Facet pump is not the problem. Dropped the tank and found the pick up was full of crap! Typical shower head screen had come apart and got sucked up.
     

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