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killerbee
February 2nd, 2010, 06:49 PM
Here is the situation. Every once in a while, for no reason that I can figure, I lose fuel command. Here is a screen print and the log is attached. The cursor is on the event. The loss occurs beginning frame 467.

I'll bet this is happening to a lot of you. Unexpected power interuption. See log below the pic.

http://forum.efilive.com/attachment.php?attachmentid=7114&d=1265179738

duramaximizer
February 3rd, 2010, 01:34 AM
Yep, pretty much sums it up right there. Annoying as heck. I thought I was the problem.

bballer182
February 3rd, 2010, 02:23 AM
Whoa... thats pretty interesting. Does it do it in stock for as well?

killerbee
February 3rd, 2010, 02:29 AM
I guess it could be a downshift torque event, but that seems like extreme defueling.

killerbee
February 3rd, 2010, 04:28 AM
Whoa... thats pretty interesting. Does it do it in stock for as well?


Yes. however there is a difference. Here is a stock run. MM3 falls off but look at how pressure doesn't nosedive.

I noticed that the pressure transient table is higher than the low table. Could it be that shifts use the transient pressure table? Just throwing out possibilities.

http://forum.efilive.com/attachment.php?attachmentid=7118&d=1265214480

killerbee
February 3rd, 2010, 08:57 AM
We really need a laptop trqref PID that will show some torque correlation to these observations.

The LBZ PID does not work on LMM. Ross, please help?

bballer182
February 3rd, 2010, 12:37 PM
Yes. however there is a difference. Here is a stock run. MM3 falls off but look at how pressure doesn't nosedive.

I noticed that the pressure transient table is higher than the low table. Could it be that shifts use the transient pressure table? Just throwing out possibilities.

http://forum.efilive.com/attachment.php?attachmentid=7118&d=1265214480

So this event is or is not happening during a shift?

killerbee
February 3rd, 2010, 01:08 PM
It should be clear from the rpm curve. Looks like a 6 to 4 shift.

bballer182
February 3rd, 2010, 01:42 PM
So you are just experiencing defuel during down shift then? thats a pretty big defuel. did you call it names and curse at the truck before driving and it's just getting back at you now?

GMPX
February 3rd, 2010, 04:36 PM
The LBZ PID does not work on LMM. Ross, please help?I hear your plea's, I do!
What is the PID name on LBZ?

killerbee
February 3rd, 2010, 07:12 PM
Engine Torque Reference ....Diesel LBZ/LMM ....GM.ENGTRQREF_DMA


Thanks!

duramaximizer
February 4th, 2010, 02:15 PM
X2 Thanks!

killerbee
February 5th, 2010, 06:24 AM
Ross, while on this topic, with several dozen (LBZ) logs to back this up, the logged engtrqref dramatically exceeds the B1115 values, perhaps a calibration issue?

At 0 throttle the disparity is about 40 ft-lb, and this disparity grows to 140 ft-lb at 100% throttle. This is using TP% for logging. I validated this claim with both my own tuning, and stock tuning also. Let me know if you need any more data.



Again this is LBZ. Former discussion is LMM, where this trq PID is invalid.

duramaximizer
February 7th, 2010, 11:28 AM
I have not been able to make a torque pid for the lmm work yet either.