5,6,7,8 misfire

[MarkoPolish]

2014 M6 went into limp mode after driving it like I stole it.

Changed plugs, coil and injectors

Have misfires in cylinders 5,6,7,8

Air blowing out of oil filler pipe

A little oil on the tip and threads of the spark plugs in cylinder 6,7

I read that possibly the ecu could of been fried but I don’t see how the ecu would have anything with air blowing out if oil filler cap

Going to do a leak down test, combustion test, smoke test and check the cylinder walls with a scope, I’ll you know what I come up with.

If anyone could give me some input or knowledge of these issues that would be greatly appreciated.

Thank You