I use anti seize when installing plugs. Partly based on some crazy high torque values to remove.

I have a small impact wrench that I will used to release frozen parts and it’s less likely to strip than high torque however if the ceramic breaks it’s absolutely imperative that you find every crumb since BMW engines are interference engines. A buddy of mine didn’t notice that the ground electrode broke off a spark plug and fell in and now he’s got a dented rod bearing and the lovely associated knock.

I was chasing seemingly random cyl misfire on wife’s x until I swapped out two of the coils and additionally ran some Lucas injector cleaner. Problem finally disappeared.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)