159 Cruiser and
AO Silver Member
Join Date: Jul 2012
Location: United Kingdom
It is only natural that the engine is slightly smokier after the DPF (it is a diesel PARTICULATE (i.e. soot) filter after all) is removed.
I certainly noticed a large black cloud behind the car the first time I booted it, but it has not reoccurred since.
I believe removing the DPF allows that much extra flow through the system that it blows away the proverbial cobwebs that have collected over time.
The EGR blanking will actually decrease the black smoke (soot) production, the soot the EGR puts back in the cylinders acts a kind of nucleation site for soot (i.e the soot forms more easily in it's presence).
159 1.9JTDM Ti and Giulietta 2.0 Veloce
ex: Punto 55s, Golf Mk5 1.4FSi, A3 (8P) Sportback 2.0TDi SE, A4 (B8) 2.0TDI S-Line, 306 HDI Meridian