Recurring misfire, sooty spark plug, swapped coil - bad injector?

[Kodachrome 146]

New to me, bought an X6M 2010 (S63 original engine, ie not TU), swapped out the original plugs (Bosch, M branded!) for the NGK version thats one range cooler (as recommended practice for the S63). 

When removing the original plugs all looked fine bar one, it was black and sooty. 

 

Now the same cylinder (6) is black and sooty and I can feel a misfire plus OBD picks up one on Cylinder 6. Car now in limp mode and CEL on. Since I swapped out the Coil already (no difference) I assume this is a bad Fuel Injector? Its running Index 7 all round. Any thoughts?

Edited June 17 by Kodachrome

[Eagle 1548]

Appears to be but did have misfire and codes before the new plugs? No wiring disturbed? I probably would of done compression check while the plugs are out

[Kodachrome 146]

23 minutes ago, Eagle said:

Appears to be but did have misfire and codes before the new plugs? No wiring disturbed? I probably would of done compression check while the plugs are out

Well I had no reason to do a compression check from a drivabilty perspective. And don't have the tool. But yeah good point. 

 

Was fine beforehand, only clue was that spark plug. Several brittle original crankcase lines broke during the process which is causing other or similar issues too.