Well, my 06 Jetta TDI (pre-cheat) was supposed to be certified to around 0.7 g/mi of NOx. It also did NOT have a deSOx cat or a particulate trap like the newer cars do, and had a simpler fuel system (pump/unit injectors) that does not have the level of control over injection events that these new commonrails do.

The Tier 2 Bin 5 tightening of NOx standards was far more than incremental. It was radical, which is why the plaintiffs here like to use “Exceeds between 10x and 40x the limit” instead of pointing out that the limit is absurdly close to zero and they’re not putting out anymore NOx than cars were legally emitting 10-15…