Tune issue on Duramax LMM truck

[bondurch]

My tune issue is this. Currently I run two different tunes that work absolutely perfect. A third tune that I attempt to run “a race tune” will not let my truck run properly. I believe it goes into limp mode either right at start up or when I have been driving for 3-5 minutes. The truck just starts sputtering, blows a bit of white smoke and has absolutely no go power. I may get 5 mph out of her when she is acting up.

Does this sound like limp mode and is there anyone who would like to take a look at the tune to help me diagnose the problem. I need more qualified eyes.

[killerbee]

beekiller at cox net

no guarantees, what are the codes

[tblu92]

Does the race tune delete the EGR valve ? I have had to re-anble the EGR on some LMM tunes as it would make it smoke white smoke and sputter badly with it tuned off-
ALSO--have you taken the DPF off the truck ?? If not the DPF filter will plug up with any tune that adds too much fuel--many handheld programmers or banks tuners have what they call a "clean tune" these tunes only add timing and no fuel but are limited to around 50-75 HP

[bondurch]

Hmmm that sounds like the issue I am having. White smoke a sputter with no power. I will look into the EGR parameters and see if that solves my problem. This tune drops a bunch of fuel and I do not have any issues with filters plugging. :)

[The Neens]

I've also had similar LMM issues with the EGR...Also, I would only contact IdahoRob regarding his tunes...I'm sure he can help you out...

[bondurch]

I did contact IdahoRob regarding the tune. He has looked at it numerous times and can not find any issues. He says it runs great on a number of LMM trucks. I do want to say that Rob is great to work with! He set me up on another tun that did work really well.

The tune I am having issues with has been bugging me for a while, and that is why I have opened the issue up to a wider audience. When I get to run the truck on the tune (for a couple of minutes) it really runs nice. Thanks for the advice on the EGR issue. I will see if I can figure out what to turn on or off. My first guess is that I need to change the EGR duty cycle parameters?

[killerbee]

It could be anything at this point, let's look at a log. That should handily answer your question. It may well not be tune related, though I see why you would come to that conclusion.

[The Neens]

I would do a comparison of the "bad" tune to the 2 good tunes...See what the differences are, then change 1 table at a time until you find the culprit...Process of elimination...

[bballer182]

I would do a comparison of the "bad" tune to the 2 good tunes...See what the differences are, then change 1 table at a time until you find the culprit...Process of elimination...

Word! that usually works...

[bondurch]

Does the race tune delete the EGR valve ? I have had to re-anble the EGR on some LMM tunes as it would make it smoke white smoke and sputter badly with it tuned off-
ALSO--have you taken the DPF off the truck ?? If not the DPF filter will plug up with any tune that adds too much fuel--many handheld programmers or banks tuners have what they call a "clean tune" these tunes only add timing and no fuel but are limited to around 50-75 HP


Thank you tblu92 you nailed it pointing out the EGR as the issue. I ended up tweaking the duty cycle and temp params, and it worked. In fact the truck works really well. :hihi: The tune is spectacular. Thanks to IdahoRob for hooking me up with the power. I guess I should read up on the egr removal.

[tblu92]

Glad it worked out for you-----When the LMM's 1st came out I had the 1st 4 tunes come back with white smoke--no power--sputtering--I tried like heck to figure it out and at the time beacuse they were so new--no one really knew much about how to tune them properly and work around the DPF filter-
The biggest problem was not having a LMM of my own to work with--So I finally called one of the LMM guys that had the issue and offered him $100 to borrow his truck for a day and use it as a ginney (?) pig--and promised to return it back to stock when done---I strarted by changing one table at a time -starting with the most important stuff 1st--and worked my way down--When I got to the EGR parameters it started to smoke/sputter---Yea !!! so from then on i just leave them be on the LMM's--- ( my favorite Duramax is the LBZ ) responds well to tuning--no problems--no codes--shifts well--learns fast--some guys around here in 2007-8 were ordering NEW trucks and paying extra for the LBZ rather than the LMM---

[rcr1978]

Whats the story with the EGR, I've been tuning mine out without the use of a blocker plate since day one and have not had any issue's yet. Do some LMM's have a certain parameter they don't like in the egr section?

[cumminsDK]

could someone please provide what year and OS they are having issues with the egr on. i have tuned several LMM's all OS 8594 and '08 '09 without any issues disabling EGR

[bondurch]

So I have an issue with the white smoke again. It's not blowing massive amounts of white smoke like my previous issue.
I have added mpi twins, 40 over injectors, and removed the egr. With my new tune the truck feels strong but the longer I drive the truck the more white smoke I see! It's fracking with me. :shock:
Should I tweak the egr values or the maf table?
Is it something with the injectors? Did I get some fuel in the oil?
I can run it at idle and hammer the throttle and see black smoke. I put it in drive and drive half a mile and the white smoke appears.
The worst part is I developed some pop pop pop air leak on a test ride so we are back to square one on the work. :fluffy:
the air leak timing increases as throttle is increased.

[killerbee]

Damn, and I just packed away the lawn darts.

[bondurch]

A simple 12 gauge with 6oz shot will give you a better chance.

[killerbee]

If you posted a log (yes, you have to work) your problem would have been resolved long ago. :)

[bondurch]

This is a new issue im having and i do have some logs. i dont see any major issues but will be happy to post logs when i get back home.