[jovolvo1]

2013 M3 coupe comp package and Dynan stage one from new purchase
78k miles. (was in for rod bearings replace at 65k, they were low wear)
Had the same issue 3 weeks ago.
No pre-fail symptoms
Climbing a hill at around 7k rpm
Right as I let off limp home engaged and car was not firing clean
Drove home 2.5 miles at <1500 RPM with clear misfire and 2 tail pipe backfires.
STRONG smell of raw and partial burned fuel.
Shut down. (stunk up the garage)
Towed to shop.
Cyclinder 7 was washed down and had light scoring.
Compression was 30% (-65%) of spec.
Dropped oil treatments in cylinder.
Currently running and driving (never over 4k rpm) with no codes or warnings.
Love this car, 2nd owner at 32k miles. Always makes me smile when I drive it.
Plan is to drive it gently for 2500 miles, and change oil, check for metal and recheck compression.
If it is recovering compression at a good rate, press on.
If not, it either hits BaT as a donor car as a run and drives in need of a rebuild/ swap. Or (more likely), the S65 goes for a 4.17, 12.5:1 rebuild from PR.
Will try to update after the 2500 miles.