Idle issues after BTR cam intall

[90clipse]

I am in need of some help, I have exhausted all my ideas as to why this truck will not return to idle without either dying or almost dying… Had a lifter failure and decided to go with ls7 lifters (DFM delete), PAC valve springs, and a BTR stage 2 cam (4deg cam limiter). I got everything installed and got Diablew to create a custom tune for me (thanks lew). The truck runs great when on the throttle and throughout the power band, but when returning to idle, it always dips down to about 300–400rpm before returning to the set idle point (if it does not die). If I am pointed uphill even slightly it will die every time and if I rev it in park it will die every time unless I feather the throttle to let it stabilize. Other than the lifter noise, truck ran perfect before cam swap. Here is what I have done so far:

- Compression check (about 190psi on all)
- new plugs/ wires (OEM)
- new upstream O2s (OEM)
- smoke tested the entire breather and intake (no leaks)
- smoke tested the exhaust (no leaks)
- cleaned all injectors and new seals
- Throttle body re-learn (autel scanner)
- O2 re-learn (autel scanner)

No matter what I do, the issue persists. Am I missing something? My first thought was that tuning needs to be adjusted at idle, but I was told by Diablew that everything that can be done as far as the tune is done (and I trust him on that, he is a very reputable tuner). Has anyone successfully tuned a performance cam on a 2019+ GMC with a T2? Any help would be appreciated.

2019 GMC 5.3 (L84)

[mikel]

can you catch a log of the issue and post it with the current tune?