What a bunch of hogwash about
What a bunch of hogwash about not being able to get the diesel cars to pass the test. Mercedes Benz got theirs to pass, BMW got their diesels to pass too. They all run Bosch diesel fuel common rail injection systems. The failure is not in the tune, it's in the SCR catalyst treatment programs and dosage. All the other diesels have considerably higher DEF consumption rates. Add 5 gallons every 5000 miles and be done with it. VW doesn't want you coming in for service every 5000 miles because the average owner is too stupid to fill it up themselves, what with where VW located the DEF spouts to refill, in the trunk, or near or under the spare tire, instead of the fueling ports like MB or BMW. People buy VW's because they love the MPGs that TDI's get. Nothing else comes close to touching them in MPG's... nothing.