LBZ: "lagging" issue

[NinjaMax]

Need a little direction here fella's

issues is when im cruzing about 65 - 70 mph and ease into the throttle to make a pass or keep speed up a slight incline. The truck will hesitate or lag a little, sometimes you can feel it lose speed then serge up (very gently, but noticeable) accompanied by a small puff of smoke. If you roll into the throttle at all lets say more then 15% it wont do it, it takes off like normal. today on the interstate i was on cruse control about 80 and just feathered the throttle about (maybe) 5% and the truck lost speed down to 75mph before it downshifted and took off like normal.
swapped out the fuel filter yesterday, still does it. Data logged tonight and checked balance rates. Balance rates are all showing healthy +-2 or less. Did 2 full throttle pulls and rail pressure is chasing commanded like it should, nothing major really stood out. The only odd thing i noticed is that the egr was coming up to around 4% even though its tuned out of operating parameters, and disabled. Im not 100% sure if there are some more helpful PED's i could be using. But its a start i guess.
truck has stock power and tuning with the exception of open vein idle and egr is deleted.

Let me know what you guys think.

EDIT egr hit 28% open at one point.

 

[rcr1978]

Is the egr physically removed or just disabled in the tuning but present on the truck?

 

[NinjaMax]

Is the egr physically removed or just disabled in the tuning but present on the truck?

Everything is stock and still installed, its just disabled.

 

[rcr1978]

Has it done this since the tune was installed or did it just start doing it with no changes to anything? If it's done it since the tune was installed post your egr settings.

 

[rcr1978]

Hows the MAF is it dirty from a pos cold air intake/oiled filter?

 

[NinjaMax]

Hows the MAF is it dirty from a pos cold air intake/oiled filter?

cleaned the maf this morning, truck has a stock intake.

B1502 min temp 319
B1504 max temp 15
B1501 control disabled

no blocker plate fyi, i know there are some flow tables i could play with but ive never had to in the past. not sure if zeroing out 1526, 1527 and 1528 would make a difference or not.

 

[rcr1978]

Here's what I ran on LBZ's with the flow tables zero'd.

I have seen egr's that will no longer hold them selves closed in the past but mostly on LML's maybe try pressure testing the intake or just toss a blocker in it.

Edit: I thought the LBZ's were particular about disabling the EGR with the switch, I always left them enabled when still on the truck and used the temp/flow tables to turn it off.

 

[Dallas S]

Unplug egr

 

[NinjaMax]

Here's what I ran on LBZ's with the flow tables zero'd.

I have seen egr's that will no longer hold them selves closed in the past but mostly on LML's maybe try pressure testing the intake or just toss a blocker in it.

ok, ill try that in the morning, i have heard that leaving it active and setting the perimeters out of bounds works better then disabling like i did. Looking at the logs it seems like when the egr opens im losing some boost directly after when rolling into the throttle, this issue is comes and goes so im starting to think they are related, the only thing im confused on is why its being commanded open if its disabled and out of bounds?

edit: i did get a CEL about 3 weeks ago, it was an EGR low flow code. Erased it and it never came back. So i think ill enable it, zero out the flow tables, and set the rest out of bounds.

 

[THEFERMANATOR]

Put a blocker plate in the egr. Anytime you disable the egr, it can open, and the ecm won't compensate for it. I ALWAYS left the egr enabled, but disabled it via the temp limiters. This way if it did push open, the ecm would see it and help compensate for it. But I fought an lmm, and no matter what I did, it was a smokey pig all around, and lazy. Popped the blocker plate in, the truck came to life, and all the smoke was gone. And this truck had been deleted before with no issues, but due to a dealership mishap, it got flashed back to stock, put my tune in it, and smoke city ensued until the blocker plate got put in.

 

[onebaddmaxxx]

As mentioned, unplug the egr. Seen them sometimes also if you are lightly accelerating up the road do the same thing. Not sure why but unplugging it will fix it. And block it also if you can

 

[NinjaMax]

ill try both ways this morning, just ordered a blocker plate to be sure. Ill report back,
thanks guys

 

[WVRigrat05]

Yep, I drove mine for a couple hitches just disabled, was fine for 1500 miles or so, then lost power on grades when you punched it and randomly you'd feel it lag, put a blocker plate in and BAM, race truck.