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View Full Version : main rate limiting?



groff
January 14th, 2012, 01:35 PM
Seem to be having some issues with 6.7 defueling...all limiters are maxed out, etc.

"sometimes" it will randomly defuel and not allow the mainrate above ~70mm3 or so. Then 10 seconds later you go WOT and its back up to ~140mm3 (normal)....Ive "sort of" been able to get around it simply by re-adjusting the main injection pulse table, but the fact is that it still randomly defuels.

The defueling does not seem to be related to current gear, boost, etc...

Has anyone else been having similar issues with 6.7's?? (auto)

thanks
Matt

groff
January 15th, 2012, 05:55 AM
Just wanted to post a little bit of a follow up on this...we started over from scratch today, logged more of the stock tune, and made some interesting discoveries. We left every table stock except main injection pulse, and timing. Left all of the stock/factory "limiter" tables stock, and left the post-injection enabled. Truck runs fine, decent power, no smoke...and most importantly, no odd defueling...

Main rate held steady at 125-130mm3. Before, we had all the limiters disabled, so main rate would hit 150mm3 or so, and then randomly defuel to 70mm3.

So maybe there are more limiters in there (or maybe something in the TCM?) that do funky stuff when the engine is above the stock max main rate?

davematthews
January 18th, 2012, 11:15 AM
It might be in the TCM/ECM communication. The torque management was giving me hell on mine. I didn't do as much research as you have, I just switched to a manual file. And it was gone. I know that's not ideal for everybody, but it worked for me.