This forum is about wrong numbers in science, politics and the media. It respects good science and good English.
I've collected some thoughts in a blog post of my own:
The #dieselgate Crusade (Part 2)
It looks like the regulators have dropped the ball with restricting actually harmful emissions like carbon monoxide while chasing after imagined threats like carbon dioxide and particulates.
Result: Some vehicles that comply with Euro 6, fail the Euro 1 test cycle with excessive CO emissions.