On the BDG thread it mentions air filters being blocked can cause black smoke, the airfilter has always been serviced properly and I still get the smoke. BDG also mention that it could be a blocked particulate filter and also other various things that the engine struggles for oxygen. See quote below.
BDG wrote:Nathanvlturbo,
I'm not convinced that it's injectors. Make sure that every single thing breathing wise related on the engine is right. I think it's more that the combustion is struggling for oxygen more than it can't burn the fuel. It's a hunch but.
Anyway, air filters, exhaust and particle filters blah blah... Try this first, if no good, we can go from there.
Good luck mate
Im guessing I have some airflow issues causing this that I will have to find. Would a decoke of the intake manifold be beneficial.. I'm up aroung the 160000 mark now so the intercooler has to come off for tappet adjustment. Is there any other causes that may be magnifying the problem?
Cheers
Skog