Piotr is right,
There are only two ways of supposedly keeping DPFs clean, one is by Eolysis (ad blue) additive and the other , which the rest of the VMs have followed is passive and active regeneration-with varying degrees of success.
The rest of the VMs regen with additional injection on the exhaust stroke,adjusting air flow and egr to clean without filling the sump up with diesel fuel. I believe there are some Mazdas out there which require draining after as little as a thousand miles--whats this about??, it makes the car unfit for purpose.
The post on the Fiat 500 which looks like it destroyed itself for similar reaons to the above, Nissan Qashqai which are sold as the ultimate'Urban'vehicle, but will completely block the dpf if driven regularly in an 'urban' environment,--all make me think that we are going to see a lot more of these problems until they change their strategy on clean diesel exhaust.
Removing the dpf, whilst getting rid of the immediate problem,is not the answer, we as professionals should be thinking of the impact diesel emissions have on the future.

*now rhere's a debate!!

Ed Kaps