2.0 tdi CBAB dsg (2009) with a smoking problem only in 1st gear

I have a passat b6 2.0 tdi CBAB dsg (2009) with a smoking problem only in 1st gear the smoke is black the car feels like its being choked until the turbo kicks in. i have blocked of the egr and disconnected it i've also tried a new egr , i've also had a dpf cleaned (a number of test were carried out when doing this) and put a camera into the dpf and it doesn't look blocked at all there are no codes im just wondering if anyone knows anything of this as i cant understand why its only in 1st gear in both sport and drive
help much appreciated