The admission was likely given that VW is already under intense scrutiny, and there are hints that things are only going to get worse. Bild claims that the US' Environmental Protection Agency has already started an investigation into Audi over the software, and will talk to VW engineers about its concerns as soon as next week. VW has declined to comment on whether or not that's happening, but it makes sense in light of the EPA's interest in finding as many cheating mechanisms as possible. And if an additional EPA investigation wasn't on the cards before, it's likely to be after this public revelation.