nitrogen oxides

The engines of today may operate along familiar principals to the internal combustion engines of yesteryear but their efficiency and cleanliness is almost beyond comparison thanks to advances in technology. Like all automakers Mercedes-Benz has put millions into developing engines to meet ever stricter emissions regulations all around the world and has made huge improvements in fuel efficiency, but its latest generation of 'BlueDirect' engines may not be available in the United States as the sulphur content in U.S. gasoline is too high. The new lean-burn 4- and 6-cylinder gasoline engines are...