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Thread: LB7 Limited to 80 mm3

  1. #1
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    Question LB7 Limited to 80 mm3

    Hello!

    I just installed a new S&S Diesel Motorsport SuperSport CP3 on my truck because my rail pressure was dropping under load. The new pump has completely fixed the issue, and I now have perfect rail pressure! However, I am unable to get the ECM to inject more than 80 mm3 of fuel. I've turned off every limiter I can find, and I'm requesting 90 with my TBIQ table, but the injected amount is perfectly limited to 80 mm3. My goal is to get it to inject 100 mm3.

    Any ideas? My latest tune and datalog are attached.

    Thank you!
    -Jay
    Attached Files Attached Files

  2. #2
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    I'd try raising the torque in B1101 for a start. You do seem to have the fuel tables high enough, but you're likely hitting some other limit.

  3. #3
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    I've already tried raising that by 10% - as well as all of the other values in that list - to no avail. I also tried raising all of the torque tables within the ECM and TCM to the torque in B1101, but that didn't do anything either.

    Thank you for the suggestion, though! Do you have any other ideas?

  4. #4
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    The only thing I can think of would be if it's going into a limp mode of some kind, but it wouldn't seem likely.

  5. #5
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    If it did that, I would be notified somehow, correct - like with a check engine light or notification in the driver information screen? Regardless, none of the Limp Mode fuel curves have a flat line at 80 mm3... I'm completely at a loss, honestly.

  6. #6
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    I just went back and looked at my logs from my LLY, and I'm seeing the same thing. 80 mm3 max. I never saw that before. Maybe it's a glitch in Efilive? IDK.

    Personally, I'd ignore that at this point and go to the main injection table if you're after more power.

  7. #7
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    I don't want to mess with pulse width like that, though. I want to be sure the ECM knows how much torque it's making at all times.

  8. #8
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    This is a glitch in the software and It probably won't be fixed, You can setup histograms and or log PW and you'll see that your's commanding more than 80. I have a feeling the EFI guys are understaffed as this has been a recorded issue for a while.

  9. #9
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    I think it's more than that. I haven't replied to this thread in a while, but I have "fixed" the issue by copying parameters into a stock file. It truly was limiting the fuel.

    It seems like there's a greater issue where the tune gradually corrupts the more you save over it. Anytime something weird seems to be happening with the engine or trans tune, I go back to the stock file and then copy in my edited parameters, and that seems to take care of things.

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