Can EFI flood?

Discussion in 'Injection Tech' started by IH64Scout, Dec 15, 2011.


  1. IH64Scout

    IH64Scout Dreams of Cub Cadets

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    i went to start the scout the other day, it was about 25*F out, 15-40 oil, and a sluggish battery. it primed, cranked 2-3 times slow, fired, stalled. then i cranked again and it was pretty SLOW, i could hear the injectors clicking away, i figured maybe if i hold the throttle? i pushed it to the floor and it fired right up. just wondering if it was maybe my thick oil or weak battery?:cornfused:

    -Jon
     
  2. Bill USN-1

    Bill USN-1 Moderator Staff Member Moderator

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    It was all of the above.
    There is a table to increase fuel when cold. A choke
    There is a table to comensate for low voltage
    And there is a clear flood mode that is enabled when you hold the throttle open when cranking that will reduce the fuel spray to aid starting a flooded motor.

    Obviously, if the system is tuned to the engine and it is properly maintained, it would reduce the chance of flooding. But if there is a mechanical issue like a weak battery, the system is designed to compensate to help the engine get going and get the person home.
     
  3. IH64Scout

    IH64Scout Dreams of Cub Cadets

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    ah hah! i figured. thank you for clearing that up. :beer:

    -Jon
     
  4. Tom Mandera

    Tom Mandera Dreams of Cub Cadets

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    My TBI 304 is overfueling when cold. Around 0-degF it'll light off when you first crank, but then will stall. Trying to start it after that is a problem - you have to go to "clear flood" and crank for a bit before it'll go again.

    Thus, I conclude I need to take some fuel out.

    Also interesting, I have a MPFI 3800 Series II in my Buick. I have flooded it before as well. Typically, this happens when it's sub-zero, and you start the car and drive a short distance (several blocks), then turn it off, and immediately try to restart (usually because I realize I've done a poor job of parking, or there's a spot closer I should get to)

    I believe the temp sensor still thinks the block is cold, while it's not as cold as the PCM thinks, and it overfuels.

    I've done it a few times in just this manner.
     
  5. Bill USN-1

    Bill USN-1 Moderator Staff Member Moderator

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    Are you looking to fix the 304?
     
  6. Tom Mandera

    Tom Mandera Dreams of Cub Cadets

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    I should. :D It's only been a few years.

    I have the BIN somewhere nearby to fool with.

    I have a new Ostrich 1.0 to fool with now, so I need to hook it up and do a few more tuning sessions.
     

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  7. IH64Scout

    IH64Scout Dreams of Cub Cadets

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    ahh well i can't wait to see when it gets a bit colder.
     
  8. Bill USN-1

    Bill USN-1 Moderator Staff Member Moderator

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    Email sent.
     

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