[Twoforty]

Codes
* 29D2 misfire cylinder 6,
* 2A43 valvetronic thermal overload protection warning.

Car is 2011 325i N52B25 with only 41000 km since new.
On original coils but plugs were replaced at 15000km during free dealer service, not due to any fault.
After driving over 200km round trip a few days ago, the engine developed severe misfire upon hard acceleration, registering the engine emissions warning light on the dash. The misfire and warning light continued for whole 100km return trip, irrespective of revs or engine load, even idling roughly at traffic lights. "Limp mode".
So the next two days the car has driven perfectly around town as though nothing has happened with no engine warning light again.
Codes were read by a friend, nothing repaired so far.
I'm reluctant to try to drive any long distance again until I figure out what the codes mean and what to fix so it doesn't run poorly on next trip.
So what's the valvetronic warning about?
Why register engine faulty one day then run fine the next?
I'm considering changing a new coil on cylinder 6 ...
What you folks reckon?
Thanks in advance.