Mercedes: RE:VITO 204 V6 DIESEL, regeneration unit, mass amounts

Question
I have a Vito 204 V6 and every now and again it pours mass amounts of blue/white smoke out the exhaust system but do not loose any power the vehicle is in Mercedes under warranty at the min but being in there for 2 weeks and they are all baffled with it could this be something to do with the regeneration unit.

Answer
Shaun,
I am not familiar with the regeneration unit. If you are not loosing fluids water or oil, I would tend to believe that the injector timing is off. And upsetting the air to fuel mixture. If a cylinder is too rich and you are not getting combustion then you would tend to get a blue white cloud because the kerosene/diesel is just getting hot enough to smoke without burning.
Hope this helps
Robert