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Thread: B0720-fuel pulse

  1. #11
    Lifetime Member GMPX's Avatar
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    On the LMM they went to the 6 pulse tables for each injection event (well, why not!).
    So you have the Main Pulse length, Pilot 1 pulse length etc.
    The Main pulse table {B0720} is still used for the main pulse time regardless of the Pilot / Post injection status. The difference in the LMM is the Pilot / Post tables have their own Pulse table unlike the LBZ which used {B0720} for all injection event pulse widths.

    Is there anywhere in your logs where the numbers do line up?
    I no longer monitor the forum, please either post your question or create a support ticket.

  2. #12
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    Quote Originally Posted by GMPX View Post
    On the LMM they went to the 6 pulse tables for each injection event (well, why not!).
    So you have the Main Pulse length, Pilot 1 pulse length etc.
    The Main pulse table {B0720} is still used for the main pulse time regardless of the Pilot / Post injection status. The difference in the LMM is the Pilot / Post tables have their own Pulse table unlike the LBZ which used {B0720} for all injection event pulse widths.

    Is there anywhere in your logs where the numbers do line up?
    One post says at wot. Which makes since due to having all but one injection. My thoughts exactly on wanting the tune as well to look at. Looking at the log and pw, unless the actual frp is not 55mpa, all injections come from this one table. Even a stock lly pw for 25mm3 is only around 900 with the same pressure. How does crank angle injector on time compare to the log?
    Last edited by abkimble; May 19th, 2009 at 05:32 PM.

  3. #13
    Senior Member camcojb's Avatar
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    Quote Originally Posted by GMPX View Post
    On the LMM they went to the 6 pulse tables for each injection event (well, why not!).
    So you have the Main Pulse length, Pilot 1 pulse length etc.
    The Main pulse table {B0720} is still used for the main pulse time regardless of the Pilot / Post injection status. The difference in the LMM is the Pilot / Post tables have their own Pulse table unlike the LBZ which used {B0720} for all injection event pulse widths.

    Is there anywhere in your logs where the numbers do line up?
    wot................................. Otherwise, no, not anywhere I can see. I log pilot 1 through 3, and have logged post injection also (never on), and I only have #1 on at cruise plus the main US, and the two add up to much less than the number in the main injection table. However, when I open the scan tool and the tune, it highlights the cell, and it's never the cell that it should be according to the log. In other words, at a 60 mph cruise I'm at 24 mm3 and 66 mpa, which in the tune would be a 1531 US, yet my main is 639, pilot 1 is 298, and pilot 2, 3, and post injection 1 and 2 are off.

    The cell that is highlighted is 20 mm3 and 190 mpa, which has a number of 790. Not sure what that means.

    Jody
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  4. #14
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    Quote Originally Posted by camcojb View Post
    wot................................. Otherwise, no, not anywhere I can see. I log pilot 1 through 3, and have logged post injection also (never on), and I only have #1 on at cruise plus the main US, and the two add up to much less than the number in the main injection table. However, when I open the scan tool and the tune, it highlights the cell, and it's never the cell that it should be according to the log. In other words, at a 60 mph cruise I'm at 24 mm3 and 66 mpa, which in the tune would be a 1531 US, yet my main is 639, pilot 1 is 298, and pilot 2, 3, and post injection 1 and 2 are off.

    The cell that is highlighted is 20 mm3 and 190 mpa, which has a number of 790. Not sure what that means.

    Jody

    It's not going to highlight the exact cell, this would require highlighting 4 cells to get to the number you post as 24mm3 and 66mpa. The only way one cell could be highlighted would be to have a commanded or actual of say 20mm3 and 60mpa.

  5. #15
    Senior Member camcojb's Avatar
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    Quote Originally Posted by abkimble View Post
    Ok so post your tune also with a log.
    cannot do that, it's a custom tune from a tuner, and although modded by me I cannot post the info. I'm just trying to find out how you come up with your numbers. It makes sense if you add up the main US, and all pilots and post injections to come up with the total in the main map, but in my case (and Killerbees it seems) they do not even come close to adding up.

    I appreciate you trying to help, but unless you're doing something different than simply adding all the above it doesn't work on mine.


    Jody
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  6. #16
    Senior Member camcojb's Avatar
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    Quote Originally Posted by abkimble View Post
    It's not going to highlight the exact cell, this would require highlighting 4 cells to get to the number you post as 24mm3 and 66mpa.
    but why is it highlighting 190 mpa at a cruise, when that's obviously incorrect? And what 4 cells? I only have the main and pilot 1 active, nothing else. Maybe they show off but really are on, I dunno.............

    Jody
    Last edited by camcojb; May 19th, 2009 at 05:44 PM.
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  7. #17
    Senior Member camcojb's Avatar
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    after looking some more, if you add pilot 2 and pilot 3 to the mix, the numbers get pretty close. Thing is, both those pilots show off in the scan. Is it possible they're not really off, or that possibly the computer thinks they're on so that's why the main US is off?

    Under what conditions do the #2 and #3 pilots become active? I don't see any controls for those, other than turning them off in the fuel pressure max pulses allowed table, but nothing that says when they're used.

    I thought post injection was for the dpf.
    07.5 4X CC 2500HD, EFI Live, MBRP exhaust
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  8. #18
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    Quote Originally Posted by camcojb View Post
    but why is it highlighting 190 mpa at a cruise, when that's obviously incorrect? And what 4 cells? I only have the main and pilot 1 active, nothing else. Maybe they show off but really are on, I dunno.............

    Jody
    I hear you on the cruise range highlite..... I just look at the data lol...

    As far as the four cells I mention, if say you want 159mpa pressure, you'd have to subtract the two cells at axis of pressure and then divide by ten then add back that number 9 times at the 150mpa cell number. Then say a quantity of 94mm3 of fuel then you'd have to do the same for the two cells that influence the mm3 axis. Then these two numbers would have be subtracted from one another and so on....

  9. #19
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    Quote Originally Posted by camcojb View Post
    after looking some more, if you add pilot 2 and pilot 3 to the mix, the numbers get pretty close. Thing is, both those pilots show off in the scan. Is it possible they're not really off, or that possibly the computer thinks they're on so that's why the main US is off?

    Under what conditions do the #2 and #3 pilots become active? I don't see any controls for those, other than turning them off in the fuel pressure max pulses allowed table, but nothing that says when they're used.

    I thought post injection was for the dpf.

    Oh no, they are off but as you say they are still being considered. Yes they have so many different tables but these tables are getting closer to reflecting actual times of 6 cycles in way less than 180 crank angle degrees.


    So, Main is in-fact main but only when all other injection cycles are off.

  10. #20
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    Is PID FRP_C the only process for actual fuel rail pressure? If so, is it calculated or measured?

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