Reuters: A truck engine is tested for pollution exiting its exhaust pipe as California Air Resources field representatives (unseen) work a checkpoint set up to inspect heavy-duty trucks traveling near the Mexican-U.S. border in Otay Mesa, California September 10, 2013. The European Commission will propose limits on CO2 emissions from trucks, following in the footsteps of the United States and Japan, and new fuel efficiency standards for cars and vans after 2020, according to a draft document seen by Reuters....