I know it's a 4l with which it started but found the thread interesting and it's a bit strange that a 4l is compliant while a newer 2l isn't.
Diesels have very high compression so they inherently have high Nox. This is why it's the EURO 6 (2014+) standard for diesels, but only the euro 4 (2005+) standard for petrols. I checked a 2008 BMW diesel for a mate and his was 0.2## for Nox so he was still out of luck.
 
Diesels have very high compression so they inherently have high Nox. This is why it's the EURO 6 (2014+) standard for diesels, but only the euro 4 (2005+) standard for petrols. I checked a 2008 BMW diesel for a mate and his was 0.2## for Nox so he was still out of luck.
I always thought it was excess combustion air that resulted in high Nox hence EGR valves injecting exhaust gas into the inlet when a reduction in combustion air is required and later the introduction of butterfly valves in the inlet manifold.?