Whats wrong with tune? Occasional studdering, smoke, then spools and goes.

[Brody]

Had this problem on a couple of trucks now including my own. My truck is a 2006 LBZ Duramax, intake, exhaust, lift pump, built trans, etc... Anyways, occasionally when cruising and getting into the throttle the truck seems to stumble and hesitate to build boost, almost feels like a defueling, but it'll do it even on a basic tow tune with the lift pump on. It'll blow some smoke in the process, but all of a sudden the boost will shoot up and it'll be all good. Egr is disabled in tuning and all of the maps for it are at 0.0. I'm guessing this has something to do with the main cal on my dsp5 which is supposed to be about 530RWHP, because i doubt the same thing would be bad on all adjustable parts of programs 1-4. So what do you guys think? Where in my cal should I look for errors? I used to think the egr was sticking, but now that it's happened on multiple trucks including one with 46k miles I'm doubting that. All of the trucks have been LBZ's with the same DSP5, just specific to their OS's. Thoughts?

[Move'n Up]

Data log and post the log file(s)

[SASDakota]

Had this problem on a couple of trucks now including my own. My truck is a 2006 LBZ Duramax, intake, exhaust, lift pump, built trans, etc... Anyways, occasionally when cruising and getting into the throttle the truck seems to stumble and hesitate to build boost, almost feels like a defueling, but it'll do it even on a basic tow tune with the lift pump on. It'll blow some smoke in the process, but all of a sudden the boost will shoot up and it'll be all good. Egr is disabled in tuning and all of the maps for it are at 0.0. I'm guessing this has something to do with the main cal on my dsp5 which is supposed to be about 530RWHP, because i doubt the same thing would be bad on all adjustable parts of programs 1-4. So what do you guys think? Where in my cal should I look for errors? I used to think the egr was sticking, but now that it's happened on multiple trucks including one with 46k miles I'm doubting that. All of the trucks have been LBZ's with the same DSP5, just specific to their OS's. Thoughts?

If the physical EGR is still inplace but you want it closed. Turn the EGR system back on and set the EGR function rational to unobtainable set points. If you aren't tracking what I am saying post the tune and ill make the changes.

[Brody]

Sorry I forgot to post back on here. I get what you're saying, set it the maps to stock and then systematically delete cells until I found my problem. I ended up throwing an egr plate in and solving my issues. Thanks!

[SASDakota]

Sorry I forgot to post back on here. I get what you're saying, set it the maps to stock and then systematically delete cells until I found my problem. I ended up throwing an egr plate in and solving my issues. Thanks!

Actually it was far simpler than that. Glad you got it taken care of one way or another!!

[Brody]

What would you suggest for someone without a blocker plate? Other than just leaving the egr on?

[SASDakota]

I already explained how to do it... Short of your posting a tune and me actually showing you, not sure how else to explain it...

If the full EGR hardware is still in place and plugged in, leave all EGR system controls and DTC codes on. Then set unobtainable goals for which EGR is to function. The stepper will then have full PID loop functionality but only uses it to hold closed.

[Brody]

Ok I'm following you. Give me an example of an irrational value that you set a whole map to. Also, I set the parameters in the egr to 300.1 degrees coolant temp for turn on and shut off, not sure if that would help, haven't tried on a truck without a blocker.