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).
392_TUNE_02-07-2024.hpt Current tune
02-07-2024-ECM-O2-TEST-1-AS-IS.hpl First log last night without changing anything
02-07-2024-ECM-O2-TEST-2-DISABLE_VEB2_TUNE.hpl Second log last night with enabling/disabling ECM 2102 VE Table 2 Disable
02-07-2024-ECM-O2-TEST-3-AS-IS.hpl Third log last night after reverting ECM 2102 back to original state
02-07-2024-ECM-O2-TEST-4-SWAP_B1S1-B2S1.hpl Fourth log last night after swapping the upstream sensors of B1/B2
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