The engine design of many new cars and light trucks today is close to meeting the latest pollution standards that will require vehicles to emit fewer harmful particles over their lifetimes.  In 2012 California approved standards to reduce emissions from passenger cars to 3 milligrams or a millionth of an ounce, per mile over the 2017-2021 automobile model years.  U.S. EPA has proposed the same target and expects it to remain consistent for 150,000 miles of a vehicle’s lifetime.  In the meantime, car manufacturers have been fitting more cars with GDI (Gasoline Direct Injection) technology, which boosts fuel efficiency by injecting gasoline straight into vehicle’s combustion chamber.  When the particle emissions from two GDI vehicles were tested, the emissions hovered near or below the limit set by the new California and EPA standards over a lifetime of 150,000 miles.

Source: American Chemical Society (2013, October 16).  Engine technology on the road to meeting emissions standards – Science Daily.  Retrieved