Can you add to your signature what mods you have on the truck? I know on my truck I run out of fuel at WOT on the top end with my big tune.
LLY: Wont boost over 30 lbs with EFI tune and HTT turbo
- Thread starter Ben46a
- Start date
what's with the pilot timing spiking and main timing is diving when the defuel occurs? Those are probably correctly following the timing tables based on the fuel, right?
Sure is a funny situation.
Sure is a funny situation.
dont know on the pilot but main timming will drop because the commanded mm3 has been lowered.... by whatever table/ tables is causing this .
because when the main rate drops below 85 mm3 (for whatever reason, whether you let your foot out of it, or there was a severe defuel) pilot turns back on.
Its not a timing or fuel pressure problem.
Something else is forcing the main rate to drop, and of course when the main rate drops and jumps around, everything else (timing, etc...) follows it because basically duramax tuning is centered around whatever the main rate is.
ben
OK, if it isn't the fuel supply issue, what about the speed limiter? Has that been removed from the tune seeing how your speed is right about where this defueling/loss of fuel issue occurs in the log?
Also, boost only builds depending on the load that the engine has on it, and the mapping characteristics of the turbo itself. Hope this helps.OK, if it isn't the fuel supply issue, what about the speed limiter? Has that been removed from the tune seeing how your speed is right about where this defueling/loss of fuel issue occurs in the log?
Ben has been tuning Dmaxes for a long time and he stated that many profesional tuners have not been able to figure this out either ... i know your only trying to be helpful .
i dont think it is an op# problem. while it is possible i doubt that larry, ben and myself have the same op#. and actually i know larry and I dont have the same #. i suppose it could be a problem in more than one os
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just trying to throw some idea's out there ... only reason behind it for me was not all lly's have this issue so o.s. popped in my mind ... like i said just a thought .
it could be possible. the only thing that i did to try to help was look to see how low it goes in mm3 on the defuel and then go to my main pw table and drag teh pw that i wanted to those cells. that way i dont loose the fuel when i get the defuel
I have not tried a different operating system. Im running DSP2.
I should try running a single tune with my factory original OS, just for grins to see if it does it.
3,100rpm is the magic enabler it seems like. Below 3,100rpm everything is "normal", but starting at 3,100rpm or so it becomes completely unpredictable.
The strangest thing is I can do multiple back to back runs, and it always acts differently every time. WTF!!???
Those big power LLY's, I wonder if they just run with totally maxed out torque tables? This would not be streetable at all, but it technically would bypass the defuel.
It seems when the ECM defuels, it defuels to a torque level. From my logs, Ive discerned it defuels to somewhere around ~350 ftlbs, because if I look at my torque limited inj qty tables to the mm3 that it defuels to (say, 70 mm3 for example), if you cross reference 3100rpm and 70mm3, it falls right in the 350-400 ft lbs range.
Of course you could set the tq limited inj qty table in the 150-700ft lbs range at 3100rpm to 100 mm3 which would probably bypass it, but it would make for horrible part throttle higher rpm shifting. There must be something else that we cant find yet.
ben
I should try running a single tune with my factory original OS, just for grins to see if it does it.
3,100rpm is the magic enabler it seems like. Below 3,100rpm everything is "normal", but starting at 3,100rpm or so it becomes completely unpredictable.
The strangest thing is I can do multiple back to back runs, and it always acts differently every time. WTF!!???
Those big power LLY's, I wonder if they just run with totally maxed out torque tables? This would not be streetable at all, but it technically would bypass the defuel.
It seems when the ECM defuels, it defuels to a torque level. From my logs, Ive discerned it defuels to somewhere around ~350 ftlbs, because if I look at my torque limited inj qty tables to the mm3 that it defuels to (say, 70 mm3 for example), if you cross reference 3100rpm and 70mm3, it falls right in the 350-400 ft lbs range.
Of course you could set the tq limited inj qty table in the 150-700ft lbs range at 3100rpm to 100 mm3 which would probably bypass it, but it would make for horrible part throttle higher rpm shifting. There must be something else that we cant find yet.
ben
will the base throttle injection table( b0727 ) over ride the torque limmiting tables ? i know it override's most other limmiting tables for camanded mm3 in my truck ? i am shure you've tried it already but just a thought . on secound thought i know the tcm defuel tables over ride the base injection tables .
Can we log the engine and trans at the same time now? I remember a while back it was not possible, has something changed since then???
Being able to log the engine and trans simultaneously would be helpful here.
Those above are TCM logs. In my opinion these defuels are not TCM related. There is a difference between when the TCM asks for a [shift] defuel and when the ECM does its goofy stupid random defuels.
On an unrelated note I also pointed out the TCC lockup issue. It appears there is another table in the TCM that prevents lockup until TCC slip rpm drops below ~550rpm or so. So if you have a loose converter or a lot of power, thats why your converter takes forever to lock.
annoying.
ben
no. Throttle base inj qty gets completely ignored when these defuels happen.
I asked before but no one seemed to know...
WHAT is driver demanded torque and WHAT can affect it BESIDES my right foot? This is really a question just for the efilive guys though...
ben
interesting ...... that is funky , are we ever going to get the tcm table for the lock up slip difference ? it would make alot of people happy ... cough cough .... in case cindy is listening , sorry for your troubles Ben i can see you've spent a ton of time tracking this down
, sorry for your troubles Ben i can see you've spent a ton of time tracking this down 
what about lowering (D5194) maximum torque reduction requested in the tcm, When this was in beta mine was set to "0" and it shifted real nice, but ended up cooking the c-2's and c-3's. Stock is set at "89", there is a wide range to play with between 80 and 0.
larry on a different not look at B0793 in the tune that you sent me and then look at the same table in one of your tunes. i am not sure but i think this table has to do with the lag when stabinh the throttle