need help, O2 voltages going crazy, dont know why (logs attached inside) 2016 C7Z

[Z06John]

So, I've been experiencing this problem for a little while now and it's been getting progressively worse. Idling and steady cruising are all fine...heck even WOT seems to be normal (once you get in the higher RPM range) but when I'm moderately accelerating (not even enough for the Alky Control meth to come on) I'm getting this shuddering. it almost feels like every other cylinder is cutting out. This usually happens from somewhat down low and as the RPM's getting into the higher range it clears up for the most part. When this happens, you can definitely not only feel it, but you can hear it out of the exhaust. Also, when accelerating, it's not even close to losing any kind of traction so it's not the nannies kicking in, but it almost feels like it. I did turn them off and it's the same thing. Anyways, I've logged a few runs and noticed that my O2 sensor voltages are all over the map, like crazy...there's no way that can be right. I'll attach 3 logs with the last one going just about WOT for a bit.
I appreciate anyone's help here.
Mods are: cam 32% lobe, aux low side fuel system, stock high side pump and injectors, Cordes 5" CAI, Alky Control meth, LT's with no cats, etc,etc all in a 2016 Z06.
july 25 run.hpl1.hpl2.hpl

[Z06John]

I'm far from an expert reading logs, so maybe this is normal for the O2's (the dramatic up and down swings) but I'm just looking for which direction to go as far as troubleshooting goes, either spark or fuel related. I tried switching tunes from 2 separate tuners and the same issue is still there. I'm just not understanding what is going on here...as you can see in the hpl#2 run I'm just steady cruising and everything is smooth and then giving it maybe half throttle it starts sputtering pretty bad. Just looking at that same log, focusing on the part where I'm accelerating (I'm giving it like half throttle) it's showing the accelerator pedal position at 51% but the throttle position is showing 99.6%....that can't be correct, can it??
Can anyone take a look and give me their thoughts of what could be happening here, I would love to get this figured out and fixed, I just don't know where to start.

[Baja38ss]

Funny you mention this because I'm having the same issues with my 15 Z06. I did change out B1 oxygen sensor and still the same issue. I thought it might of been the MAF getting heat soaked but no luck there either. I'm hopefully going to get to the other sensor today just to rule it out. My downstream 02 are turned off.

[Z06John]

Yeah, like I said maybe those wild swings are normal, I'm not sure. I'm trying to find other people's logs where they're moderately accelerating and see if those two PID's line up, the accelerator position being the same or near the same as the throttle position. On mine, the gas pedal is at half but the throttle position is showing wide open (99.6%). If that's true, then maybe the studdering is from it running really lean?

[Baja38ss]

I didn't see anything in the Knock on mine for a lean condition. I seem to have more of a separation between the two 02 sensors then you do, but they do fluctuate a good bit. I also change my plugs out with no difference so you can rule that out. I'm starting to wonder about coils, but I don't have any CEL on either. Could do injector balance to rule those out, I guess. But mine seems to be getting worse as well. I didn't look at me throttle position yet.

[RaceReadyTuning]

Your airflow models are a ways off, and the car is misfiring at WOT. Either spark blowing out or another reason.
Looking at the log, it looks like the torque model is way off also. And the Throttle body needs to be set up. Seeing full throttle at 50% pedal is going to fight you tuning the vehicle.

[GHuggins]

I haven't looked at any of the logs as I'm in a rush, but this is almost always plug wires or plugs when dealing with this type of issue. It's more than likely missing. Wires and plugs can be cheap enough and are easily damaged even on new installs. I would start there.

[Z06John]

thank you both of you guys for offering info. So obviously, the pedal position and throttle position should be in the ballpark of one another, correct? Again, when I applied half throttle (50% gas pedal) then the actual throttle position on the NW103 should be relatively close, so would bad plugs and/or wires cause this anomaly? I'm just trying to wrap my head around why those 2 things follow each other when idling and steady cruising and even when I'm first applying moderate throttle but it's like once it hits a certain point then the throttle body just goes to the full open position for no reason. Even with 2 totally separate tunes from 2 totally separate tuners this same problem occurs, that's why i was thinking maybe it's something either mechanical or electrical. i just checked all of the wiring and pins/hardshells around the throttle body area (there's like 5 connections right there that come off of the driver side fuel injector harness. I don't expect anyone to fix anything as far as the tune goes but I'll attach my current tune maybe one of you guys could take a quick look and see if you see anything CEL's or misfires that would show up? and also, why does this just happen while moderately accelerating in the midrange but yet under WOT it still pulls good up top and puts down decent numbers?

I would gladly pay someone to help figure this out, even if they just make a fix in my current tune.race mod tune c7 6-21-2025.hpt

[GHuggins]

It's all about cylinder charge and load on the ignition system. Doesn't have anything to with pedal exactly per say. Stumbles at idle or while idling around are good indications. Stalling. Idle dips. Breaking up with sudden intake charge take ins such as throttle opening when engine load increases. All of those increase the load on the ignition system. Wires are cheap. usually 40 for a decent set of motorcrafts at advance. if plug torque goes over 18lbft it can distort and crack porcelain. I'll take a look at the log in a min, but what you are describing sounds just like misfiring.

[GHuggins]

July 25 log has missing on bank 2 and bank 1 a little on tip in. Also looks like you're using an older version of my channel config that i posted a long while back

[GHuggins]

Log 2 almost looks like torque management - could possibly be multiple cylinder misfires, but whole bank pretty much dead. This is common with TM on the ZL's if spinning, so are tire sizes right???

[GHuggins]

Log 1 is showing timing cuts at cruise. This is usually again because of torque management and usually due to torque models not being right or balanced to one another in this instance.

So in conclusion, I still think you have a wire issue or something ignition related, but you also have a TM issue causing problems.... I haven't looked at the tune. They're usually always wrong on the torque models or air models, so i don't bother anymore i would check obvious things such as tires, plugs and wires and then traction control on and off first before moving forward. A bottle of water per plug area is a good check while it's idling to look for misfires and no, the counters won't always show.