6L80 - DIY Rebuild - Good for 4000 miles, now first slipping

Hi all, first post, first 6l80 rebuild and first HPTune.

About 4000 miles ago I rebuilt the 6l80 in a '15 Yukon. She was doing great until just recently. Now, on the very first acceleration, just after starting the engine, first gear engages fine, starts to go, then feels like it slips for a bit, then goes fine for the rest of the drive. As soon as I turn the engine off, then get back in to go, she slips in first for a bit, then goes OK.

Everything was replaced except for the Techm, but when it started acting up, I replaced that too, but had no change. So I bought a HP Tuner and performed the suggested tune from this HP Tuners 6L80 tuning video https://www.youtube.com/watch?v=KhPB7-RWQbY . But sadly, there was no change for the first gear issue.

I have a "post tune" log file at: https://thechristisens.com/publicdoc...PostChange.hpl
I couldn't get files to upload on this site for some reason.

I'm not quite sure what I am looking at yet, and am hoping someone may see something obvious.

Thank you very much for your time! Matt

The one thing that stands out for me, is the PCS 2 pressure pulsations (in yellow). It only does this after engine start and initial acceleration.

Attachment 162317

Was collecting some logs last night, just looking at how things were operating and trying to get a clue on what could be wrong. On start, first transition to drive, the initial acceleration in first is fine for a second, then PCS2 pulses 6 times which causes a slipping or loss of power feel, then everything is fine after that. BUT, if on start and first transition to M1, then acceleration is fine and there is no pulsing of PCS2. Once at shift from 1st to 2nd RPM I run it up to M6 or Drive and all is good. So there is something different between acceleration in D1 and M1, which is strange to me right now.

It looks like there are four pwm pressure control solenoids and two on/off solenoids. I need to figure out how the hp tuner layout descriptions (PCS1, 2, etc...) match to the actual solenoids so I can line it up to the solenoid operation chart. From there maybe I can figure out what the hey is going on.
Attachment 162560

https://www.youtube.com/watch?v=NmTSRoC4NzA

For comparison, a video may help, but there are no generator signals there
I found there the switching of L/R by a combination of sol456 and solschift2

PS...probably again a leak in 35R which should fill 35R but it turned on 35R....