Black smoke and loud banging from engine is my x5 dead?

[g300d]

Black smoke and lots of loud banging? Sounds like a heck of a party under your hood man!

But seriously, dont keep running it to find out the problem post mortem. If it suddenly was normal after a bit like you say, it may be salvageable.

As mentioned, read the codes, something like that would probably leave a few.

Have you looked under the hood and underneath? Anything off visually? How are the fluids? Still level and normal color and consistency?

[jdd]

Sounds like the harmonic balancer might have let go which is not uncommon on the M57.
The black smoke may have been the rubber if there was slippage between the inner and outer parts.