Diesel car engines like this one in a 2012 Volkswagen Golf are among those that include software that circumvents EPA emissions standards for certain air pollutants. Patrick Pleul/DPA/Landov hide caption

itoggle caption Patrick Pleul/DPA/Landov

An employee serves customers in a Chipotle restaurant in Washington, DC on September 9, 2015. Chipotle, the burrito chain whose rocketing growth has fast-food giants like McDonald's reeling, is not slowing down: it plans to hire 4,000 new staff in one go. Andrew Caballero-Reynolds/AFP/Getty Images hide caption

itoggle caption Andrew Caballero-Reynolds/AFP/Getty Images

A classic Lincoln Continental convertible is seen in Washington, D.C., in June. Sonari Glinton/NPR hide caption

itoggle caption Sonari Glinton/NPR