2006 9900Xi with a cm870?

[stevespeed]

Not 100 percent sure on engine (it is red) The engine is a slug and smokes black under a load. My boost gauge will go up to about twenty eight and then drop down to about 15. The Cummins guy checked and said my Turbo was ok. He also changed the fuel metering actuators and EGR Valve. $4000.00 later still runs like crap. Could it be Turbo Actuator or timing Actuators? Everyone has just become a parts changer. HELLLPPPPP !