we are all driving different cars based on 'local' emission laws, where all our emissions contribute to THE single most important global 'issue', doesn't it?
Emissions in this case was the 'regulated pollutants' CO/HC/NOx, not the so called 'emissions' of CO2 which is just a byproduct of the amount of fuel burnt, not the quality of combustion or aftertreatment (catalyst).
The EU test cycle is different to the US is different to the Japanese (the rest of the world uses one of these or mild variations from it) and thus dictate different responces (why we have had 2 cats on all our cars here while the japanese just had a catted D/P for example).
As an example, when I worked on Supercharged Range Rover, it passed Japanese and US no probs as the Japanese cold test cycle is easy with very high limits, while the US cycle has an aggresive first acceleration that puts lots of heat into the catalyst very quickly, the EU test cycle requires rapid catalyst heating but has a very gentle and short first acceleratuion, we could get the cat active and then it would 'go out' again during the following idle, after about 3 weeks of testing (2 cars twice a day, say about £500/test!) we (credit were credit is due, I not we :icon_biggrin
finally found an innovative solution.
Simon
