

The dumbest part is that after I got my car updated (the Passat only needed a firmware update) the fuel economy was not even one MPG worse. It’s been a decade and I’m still regularly getting slightly better than 50MPG on the highway and low-30s in the city. There was no reason to cheat.
It’s my understanding that the cheat was in all TDI models, but the smaller Jetta was particularly bad because it didn’t have a urea system and the fix for that model was to retrofit one. My Passat may have needed a more robust urea injector and not just software, but I can’t remember now. Either way on my year/model the fix was barely noticeable.