2004 X5 E53 3L D- turbo or injektor problems?

[norway2]

Hi
Have problems with the car (2004 X5 E53 3L diesel), it first looked like it had caught fire but it turned out that the smoke came from the exhaust, the engine has before this gone a little tough and the whole car has shaken a little when it has gone low rpm. first thought it was the turbo but checked it today and it seemed that it rotated nicely and that the paddle wheel went nicely around. Anyone experienced a similar problem? can this be due to the injectors?
On iobd2 scan it says something about Smooth running controller- not sure what it is? See attached picture