SAN FRANCISCO - MAY 18:  Thomas Zielin (L) helps a customer with an emissions test at Smog Queen May 18, 2009 in San Francisco, California. The Obama administration is expected to announce a plan that calls for raising automobile fuel economy to 35 miles per gallon by 2016 and reducing greenhouse-gas pollution. Getty Images logo Getty Images 8 months ago

SAN FRANCISCO - MAY 18: Thomas Zielin (L) helps a customer with an emissions test at Smog Queen May 18, 2009 in San Francisco, California. The Obama administration is expected to announce a plan that calls for raising automobile fuel economy to 35 miles per gallon by 2016 and reducing greenhouse-gas pollution.