Missing STFTs B2 GPEC2

Vehicle: 2013 Ram 1500 4x2 CC (GPEC2)
Engine: SRT 6.4 with MMX NSR Cam (220/232 @ 0.050 & 0.597/0.553 LSA 112.5), ported 6.4 truck intake, 1 3/4" ARH LTs, Off-Road Y
Transmission: 3600 Street Edge Converter, 8HP70 Swapped w/ SGA Harness/Computer (originally had 65RFE)

GPEC2 History: Originally tuned stock engine by Diablo, bricked the PCM, Diablo unbricked and re-flashed stock tune, flashed custom HemiFever tune on Diablo, ran okay for a few months. Engine swap time, using Diablo I flashed back to stock in preparation for HPT and engine upgrade. It was then tuned by local tuner using HPT who was affiliated with shop that swapped the engine (package deal). I quickly blew-up and rebuilt the 65RFE transmission and the rebuilt transmission had issues and I had a distant friend of a friend who worked at a dealer repair the shoddy transmission job and in the diagnostic process flashed the PCM back to stock using WiTech. When I picked it up from distant dealer, I flashed my most recent custom HPT tune, **naively** not saving the stock WiTech OE tune before doing so. The local shop affiliated tuner was garbage with response times and after extensive research didn't have the best reputation, couldn't even give me my stock tune file, so I looked elsewhere. I found a well known remote HPT tuner, who happened to be local, fix the shop affiliated tune. I quickly smoked the rebuilt 65RFE while the tuner and I were going back and forth logging and tweaking and it sat for over 1.5 years while I figured out which transmission to swap and gathered parts, etc. I landed on using the harness and computer from Sound German Automotive (SGA) to swap in an 8HP70 and he performed some proprietary backdoor modification(s) to the most recent remote HPT tune (I assume using HPT Pro maybe?) to turn off the 65RFE transmission features of the HPT tune, enable P/N/D over CAN, etc., since the 8HP70 has its own TCM, which I am sure you're aware. I then reconnected with my well known local/remote tuner to pick back up where we left off and quickly dial in the ECM tune and then separately tune the TCM since it is controlled by a secondary OBD port from the SGA hardness/computer.

The Issue: I have had some free time recently and was going to tighten up the VE tables and really dial in the fueling tune myself. The truck actually drives great, I am experiencing no real drivability problems, just seemingly wild swings of the trims (B1) that I would like to tighten (more of a self-improvement continuous education challenge than a tuning issue). The only problem, STFTs on B2 are non-existent, it always shows 0. During the 1st tuning session with current well known local/remote tuner, he noticed something weird with the O2s (probably this issue) and suggested replacing upstream sensors on both banks, they were stock with around 170K miles so it made sense. I used OE NTK sensors. The downstream were and still are the original OE NTK sensors with just shy of 205K miles and O2 mini-cat simulators.

O2 Sensor History: Looking back through the first logs with HPT and original shop affiliated tuner, this was always an issue. In my first 20 minute log, the STFTs on B2 moved from 0 maybe 4 times. With my first log with the good tuner, the issue is the same, STFTs on B2 moves from 0 4-5 times over a 40 minute drive, usually corresponding to a big dip in load. The sensors for both banks seem to be working, all 4 show fluctuating voltage on the 5V scale, I am guessing this is a bias reference or something as the SAE PIDs on these logs show the standard 0-1V range. STFTs for B1 are doing their frequent adjustments throughout all the logs, only inactivity on B2. More recent logs show that B2S2 was staying near 5V and when I logged/worked last night, both B2S1 and B2S2 were staying near 5V with B2S1 SAE pegged at 1.273V the entire time.

Other Information: I now only occasionally data log if it has been a while or if I am trying to figure something out, but I don't do it regularly anymore. I still have the Diablo, it is a Trinity 2 EX and I use it just for monitoring, it is great for that - but hopefully not screwing anything up, it should be read only. Along with the stock (4) sensors, I have an AEM wideband (AEM 30-0334) behind B1S1 in the y-pipe that is sandwiched between the OBD port and the mpvi2, when I remember to hook it up. The STFTs on B1 seem to fluctuate at an expected frequency and the LTFTs for both banks is the same, even though STFT for B2 is 0. On my VCM Scanner layout (slightly modified from what was provided by my well known local/remote tuner), the values in the channels and the values in the charts/gauges don't necessarily align. I think that is because the channels are the direct PIDs vs the charts and graphs were setup as "sensors" - so this is confusing me a bit as I don't necessarily know where the VCM Scanner is pulling the sensor data - I can post screenshots or export my configs to clarify what I mean if this isn't clear.

Diagnostics Performed: With the recent high/static voltage values for B2 sensors, I unplugged both B2 sensors and checked power with the key on, engine off. The heating circuit (two white wires) at the plugs was receiving power, it was hard to clip/probe and read meter for exact voltage. Both of those B2 sensors were reading around 4.5 ohms of resistance across the heater. I warmed up the engine, logged it (all logs from yesterday evening attached below) and both sensors on B2 were showing about 5V while both B1 sensors were fluctuating in the 2.5-3.5V range. I tried to reverse the ECM 2102 VE Bank 2 Disable (was set to No, changed to Yes) incase the parameter was accidentally defined backwards, and it did not change anything. I was thinking maybe the B2 sensors were bad so I swapped B2S1 with B1S1 and the issues in the log did not follow, still high/static 5V values for B2 sensors and no STFTs for B2. It is leading me to believe something is wrong with the PCM.

Future Diagnostics (hopefully tonight): Compare B1 & B2 upstream sensor voltage readings directly from sensor with that of the ECM. Disconnect battery and short cables to wipe ALL capacitors/memory-banks, let sit overnight disconnected for added thoroughness as per suggested in a thread linked below.

Before creating this thread, I read these threads which gave me the idea to disconnect battery and why I provided so much history about the computer, 2017-Challenger-6-4-Auto-Fueling-problem-Bank-2, Corrupt-PCM-trims-be-wild, Bank-2-VE-Tables. I can spend all day dreaming up ideas to test but then only get an hour or so to perform actual work before I have family obligations so I was hoping to gather other diagnostic tests that I could quickly perform and see where this heads. They're all the same sensors (NTK 23161 vs 23162 vs 23165), just different wire lengths (10", 14", and 18"), should I try leavings the sensors where they are and switching the plugs around and seeing what happens? With the evidence of swapping the actual plugs unchanging, I don't expect anything to change - thoughts? Any other PIDs to log on the way home from work tonight - I know I have a lot selected, they were what my well known local/remote tuner provided and I added a few in my attempts at figuring this out?

Sorry for the long post, I tend to vomit all information available as I don't want to assume what may or may not be relevant when asking for help. If needed, I can provide much more information or logs or screenshots, etc., I have tons of data logs (374) from the past few years, but the channels vary depending on who was tuning and issues experienced over time. Just to clarify, my well known local/remote tuner has tried to help but doesn't really have any ideas, this is not a knock on him, I am satisfied with the tune provided and the money I have paid (not much).

Attachment 142696 Current tune
Attachment 142692 First log last night without changing anything
Attachment 142693 Second log last night with enabling/disabling ECM 2102 VE Table 2 Disable
Attachment 142694 Third log last night after reverting ECM 2102 back to original state
Attachment 142695 Fourth log last night after swapping the upstream sensors of B1/B2

So tonight I was able to disconnect the upstream sensors on both banks and measure the voltage. I started the truck and waited for CL and then disconnected the terminal on B1S1 (sensor that was previously B2S1), I was getting fluctuating voltage from maybe 0.40V to 0.80V, as expected. I then plugged it back in and went to B2. When I disconnected B2S1, I was getting a solid/consistent 1.18V. On the attached log I took during this process, you can see when I disconnect B1S1 (around 3:50 mark) and reconnect it a minute or so later (around the 5:04 mark). You cannot see a disconnection of B2S1 in the voltage, it remains constant at the 1.273V to the end of the log.

So I am still going to disconnect the battery later and try to reset everything as mentioned in previously linked threads but I am thinking the current B2S1 sensor (previously B1S1) is still working correctly (it was fine yesterday and months/years before) and it is just seeing a ton of fuel, hence the high voltage reading but for whatever reason, is not cutting fuels, as evidenced by the 0 STFTs on B2. Maybe something is dumping fuel on B2?? Sticking injector? They're the stock truck 6.4 injectors and have maybe 40K miles on them. The truck continues to run and drive fine. After we leave my daughter's dance class, I may try switching upstream sensors again and running this same test to measure the voltage of the upstream sensors in switched banks. I suppose I can try to get more accurate voltage readings of heater circuit, resistance of sensor heating element, etc. I also briefly visually inspected wiring and everything seems fine. It is all secure in the OE loom but not at all stressed with the unused original 65RFE wiring. I can't see any pinch points or cause for further investigation but if the battery reset trick doesn't work, I may need to investigate further this weekend.

Attachment 142711

Alright so after I got home from dance last night, everything was warm and hot and had been running for over 30 minutes on back country highways. I swapped back B1S1 and B2S1 so they're in their original locations, plugged them in, started it up, idled it for a minute or so, disconnected the sensor terminals, and measured the voltages directly from the sensors as I did earlier in the evening. While they were out of the exhaust, I measured the resistance on the heating element and both sensors showed between 4.1-4.3 ohms. The B1S1 sensor showed 0.3-0.8V fluctuating as expected - earlier in the evening when this sensor was in B2S1, it showed 1.18V after driving home from work (even warmer and longer drive). The B2S1 sensor showed a fairly steady 0.445V +/- 0.050V when measured directly - the VCM Scanner showed the fixed 1.273V the entire log from before it was unplugged and after it was plugged back in - no change.

Before I plugged the terminals back in with the engine running, I tried to measure the harness voltage of the heating circuit on B1S1 after I had measured the output voltage. I am not sure exactly how the heating circuit is programmed but when I tried to measure the voltage of the open terminal, I kept getting OL on my meter, overload, not open loop, which is something like 600V RMS protection. I don't know if I accidentally shorted it, it is pretty tight to get both insulated alligator clips in the terminal, and the ECM shut the circuit down, or if the heating circuit turns off or cycles, I need to do more research on that. I did get a P0032 after that. It was getting late so I didn't attempt to try and read the heating circuit voltage on B2S1, I just plugged everything back in and secured the wires away. I then parked it and disconnected the battery and shorted the cables together with a 3 amp fuse for about a minute. I let it sit overnight and this morning there was no change to the performance of B2 sensors and/or STFTs. They are still showing a constant 1.273/1.275V in the VCM Scanner and I am not getting any STFTs on B2. I am guessing something is wrong with the heating circuit on B2? I am not getting any codes for that either.

Any thoughts on where to go from here? I know my diagnostic methods are all over the place. I only have a basic understanding of the O2 sensor system and tend to overthink things, especially when I spend most of the day going down the rabbit hole and only getting a limited time to test things, I usually screw them up.

Alright so I turned on the PID for O2 heater duty cycle and can see for sure that the ECM is not commanding B2 to turn on. Now it is a case of the chicken and the egg, is the heater circuit not turning on because the ECM is disregarding B2 and not calculating STFTs or is the ECM not calculating STFTs because the heater circuit is not turning on?

I have poured over the tune and cannot find anything that stands out that would be preventing the heater circuit to ignore B2. I don't have any codes either making the heater system detect a fault and subsequently not start. On that subject, does anyone have any suggestions for DTCs that may be disabled/turned-off that may be causing this issue? Since I don't have a stock tune, the best I was able to do was find a 2013 Ram 1500 stock tune in the repository and manually compare the DTCs and make mine match. The person who loaded that tune states it was up to date as of 2015 but that is quite a long time ago as far as updates are concerned.

I guess I will pour through those again and turn any on that I could guess would have some affiliation with the heater circuit. I will also check the oxygen sensor harness wires this weekend and make sure there are not any shorts, just incase something is causing that side to not initialize, even without throwing a code.

This past weekend I performed several oxygen sensor and heater circuit diagnostic tests from codes likes P0032, P113E, P0133, P2271, etc. The diagnostics performed via AllDataDIY had me checking voltages at various locations/conditions, continuity in all sensor circuits/wiring, supplied heater voltages/resistances, running individual sensor heater tests via AlfaOBD, etc., and all tests resulted in the last ditch option: replace PCM (since obviously they're based on stock tuning which this isn't). All of the wiring was good, I didn't have any short to voltages or short to grounds, no excessive resistance in the wiring, sensor resistances and parameters within spec, PCM voltage outputs within spec, etc.

So for whatever reason, bank 2 does not work. I was able to turn on bank 2 heater circuits via AlfaOBD so I know the PCM is capable of turning those on but for whatever reason, the PCM is not commanding bank 2 O2 heaters and is not trimming fuel on bank 2.

I don't know which is the primary issue in this chicken or egg scenario, either the PCM is not heating bank 2 sensors and since it is not heating sensors, it won't trim bank 2 fuel due to unreliable combustion data due to cold O2 sensors OR the PCM is somehow glitched/programmed to ignore bank 2 and since it is ignoring bank 2, no reason to heat the oxygen sensors. This really makes me think it is programming issue with the ECM 2102 parameter, VE Bank 2 Disable but I already tried switching that around with no luck. I really doubt/hope the PCM isn't the issue as that would be quite the nightmare and process to replace.

Any thoughts on things to try within the tune? Also, is disconnecting the battery the only way to reset fuel trims? In VCM scanner I saw an option to reset fuel composition but that seemed more like resetting an ethanol content sensor more than the trims, can anyone confirm?

Instead of disconnecting the battery to reset fuel trims, I will use AlfaOBD unless anyone can confirm the fuel composition reset in VCM scanner.

Holy shit that's a lot to sort through. Cliff notes? I see no one has responded. Maybe be a little more brief?

TLDR

Missing STFTs on B2, always 0%
Looking back, its been that way for a while
B2 has weird voltages and no O2 heaters
Testing sensors, wiring, etc, all diagnostics tests lead to replace faulty PCM as the OEM/stock tune should be working fine
I am leaning towards something in tune disabling B2 because I can command O2 heaters for B2 with diagnostic software and they get power
I tried changing the ECM parameter 2102, disable VE bank 2 in tune, trying both Yes and No without any change.

Don't want to believe I have a faulty PCM, hoping something else in tune may be causing issues with B2. Ideas?

U have O2 sensor engine diagnostic disabled.
with diagnostic on, the pcm would tell you problems about the sensors.

there is no signal, so if the sensor and wire works, the pcm will be bad.
So a rewrite with an older setting would be good.

VE bank 2 disable is for fueling without ANN.

To the best of my knowledge, I have all of the stock diagnostics enabled. I have only been able to compare to a couple of repository tunes though as the original tuner did not save my stock file. Are there any codes in particular you are referencing?

At this point, I am fairly certain the PCM is the fault as I have isolated all (4) sensor circuits, load tested them and they only have 0.04-0.09V drop with a single 3 ohm load. When I run the heater tests via AlfaOBD, both B1 sensors brightly light up the test light while both B2 sensors are very dim and since the circuits can carry load, for some reason the PCM is not able to supply enough power to heat those B2 sensors.

I have just been doing anything I can to try and find some other fault because the logistics of a PCM replacement for my setup is fairly complicated.

the b2s1 was off in the tune file checked it with an older vcm version just activated it

Attachment 143842

Wait, so something was off in the tune file and you fixed/uploaded it? If so, thank you so much!

I can't upload the tune to test it out until I get home as I drove the mustang to work today, but I did run a comparison of the tunes and it did not show anything different? Did you adjust something I am unable to tweak?

the older versions of vcm allowed to disable O2 sensors (not anymore EPA) and i completely overlooked the secondary O2 settings one of them was off too
here's the updated file hope it works

Attachment 143854

You are the man! I owe you a million. Within the next few weeks, I was going to start the process of ordering a PCM, getting a dealer to flash the latest update, backdoor the transmission settings, purchase new credits, re-tune on the latest OS, etc. Do you know how pissed I would have been when I went through all that and it still didn't fix it?

You are a life saver! Thank you so much!!

On another note, do you know what old version of VCM you are using? I have the version from the original tuner saved (4.9.264.0) from around fall of 2020 but before I go through the trouble of uninstalling the current version and then reinstalling that, I figured I would check what version you are running.

Log showing B2 heater duty and STFTs:
Attachment 143855

I was able to install both versions of VCM suite and FYI for anyone that stumbles across this thread, version 4.9.264.0 (Beta) did allow access to re-enable the O2 sensors.

Thanks again JohnnyFW!!

awesome glad it worked i have vcm 4.8.7 and use the newest beta

new pcm and os would have worked too probably hahaha