Eng kills power completely during burnout - question

I still have a million questions, but here's one that is a real potential problem and I don't have a clue:

You know how these cars completely kill power when you try to power brake with traction control On? Well today it did it when traction control was Off and no braking. Never had that happen before.
I was just trying to spin the tires and see how power was doing with a tune I made last night that was meant to lower power at lower rpm to hook up better.

I did a couple burnouts from a roll, like 10-30mph and it was fine. I then tried from a stop and it spun the tires thru 1st, then a moment after if shifted to 2nd it shut down. I let off thinking yet another complete ECU shutdown that requires a reload to fix, but as soon as I let off it was fine. So I immediately floored it again, now moving maybe 25mph, and again it spun the tires but only for a second and shut down again. Again it was fine immediately after I let up. No CEL. I spun the tires two more times in 2nd gear at >25mph and it was fine. Wth?

Tune is attached if anyone cares, but all settings are lower or equal to other tunes that were fine, so I'm confused.
Basically I started with an old so-so tune that I knew worked and adjusted the two things in the pix to make less power at 2500rpm and below, and see how it reacts.

Attachment 119267

Attachment 119268

Put the car in dyno mode (see YouTube for procedure) for a full burnout. ESP off only partially disables traction control as you found.

It has never done this before so something different triggered it.
Side note; in dyno mode the headlights dont work. Its a rare day I can spin the tires during the day so dyno is basically a no go.

I think the headlights will work if you turn them on manually vs leaving them on Auto... IIRC.

revert to previous files and pin point your issue

Easier said than done. Tried to repeat it for a few days after but it wont do it. I even went to the exact same spot and time of day where it happened, each day, nothing.
I gave up and moved on with my tinkering.

Schnell: You're right, manual worked. I would've bet $ it wouldn't because I can remember turning the light switch back n forth trying to get it to work last year. I remember it clearly because I had to pull over and undo it to get my lights back. But I tried it yesterday and lights came On. So either it didn't work then or I managed to rotate the switch and somehow miss manual, which I can't imagine and swore that manual was the first thing I did. Normally I'd take the hit for that as being stupid but this car does lots of weird stuff so who knows. For example:
It also says "15 min" on the dyno display, which I took as you have 15 min to play and it'll revert to normal, but 20 later it was still in dyno mode. In fact, it was still in dyno the next day when I started it. So I turned it Off manually, but still in dyno. So I turned it off/on/off, still dyno. Then just Off and it finally worked.

Have you tried to check if both rear tires were spinning on your Mercedes Coupe? If it is an open diff, a one wheel peel may occur, causing the wheel to spin too rapidly for the transmission to handle, triggering an axle overspeed sensor that cuts power to the engine accordingly. You might need to get a locking differential. That means both wheels would spin at a safe RPM for the transmission to maintain normal fluid pressures.

They both spin. Its an engine/fuel shutdown, not brakes. I think I know what it is. Seems its hitting the rev limiter. The Scanner data is too slow to catch it but I raised the limit and it now it rarely does it. I still hit it last week so I raised it more and hopefully rarely is now never.
The limiter says its a "soft" limit but is not.
The tranny and its fluid has no clue if one wheel or both are spinning btw.