Hi all, thanks for all the lurked help over the years. Now I have an issue I can't solve by searching:

Car: 2010 MCS (N14/R56, ~95000km)
Me: mid-50's-age car guy, good experience fixing/restoring many and various cars and other things, good tools, reasonably clever but occasionally dense.

Wife's treasured Mini got sick. Without going into the full story, the short version is: Death rattle = new chain/tensioner. Sudden loss of coolant, tailpipe/spark plug residue, milkshake in the catch can = new head gasket. Since I'm in that deep, makes sense to do water pump, cross-pipe, thermo, trans. Edited to add: I own the correct (if cheap chinese) cam locking kit and am confident it was used correctly).

So, I replaced:
Timing chain, guides, chain tensioner, front crank seal
Head gasket (valve grind and new valve seals, decarbonized)
Water pump, cross-pipe and thermostat/housing
Valve cover gasket
Trans fluid, filter and trans sump gasket
Oil change, filter, sump gasket
Throttle body
Turbo air inlet pipe (was split)

Car started and ran beautifully after all that, but quickly began to hunt at idle and would not restart. Several codes indicated throttle position sensor. Replaced throttle body when testing revealed intermittent throttle open/close while pedal input showed correct on OBD2.

Reassembled with new throttle body, reset adaptations using Schwaben tool, starts and runs beautifully but then begins to hunt/idle poorly. Revs well on throttle input. No misfires in codes, but now seeing codes 2b02 and 2b0b (and only those).

Is it more likely the [new] throttle body failed? Or pedal position sensor?

Also, when performing adaptation resets, the scan tool instructed me to turn off Pin 15 and then turn it on again. I can't find a useful reference for exactly what is meant by that; I turned off the ignition and turned it on again for the suggested 15sec.

Pretty close to the end of my rope here, so all considered advice is welcomed.

 

Well for all those interested:
Problem is resolved. It was a single bent pin on one of the 3 ECU connections.
As I have often told my network engineering students: It's always the cable.

 

PS: Sounds as if you've been lurking around for some time, but nevertheless: welcome to the forum! :-)