That first warning came two years after VW started developing the small-displacement diesel, around the time that the two men pushing its development, then-brand chief Wolfgang Bernhard and engineer Rudolf Krebs, were telling their superiors that the engine needed AdBlue urea injection to pass US emissions. VW cost controllers wouldn't approve the AdBlue solution because it would add 300 euros ($335 US) to the cost of the vehicle. Bernhard and Krebs left the same year that Bosch advised VW about the software, two years before the engine went into production.
That's when things get cloudy. A report in Automotive News says that when Martin Winterkorn took over in 2007 as head of the VW Group and brand, he asked Ulrich Hackenberg and Wolfgang Hatz to keep working on the engine, and "[the] engine then ended up in VW Group diesels" with that problematic software still intact. No one has yet pointed any fingers at this latter chain of command, but like a game of Clue, right now they're the professors in the library holding the candlesticks.
Warnings didn't only come from the supplier: Frankfurter says VW's initial investigation has found that an engineer issued the same caution to the company in 2011. Neither Bosch nor VW would comment on the reports.