The White House is set to propose the toughest-ever U.S. curbs on car pollution. The proposed standards on cars and light trucks are expected to govern tailpipe emissions of carbon dioxide, smog-forming nitrogen oxide and other pollution from vehicles manufactured for model years 2027 through 2032. President Joe Biden\u2019s proposal stops short of an electric-vehicle mandate or ban on gas-powered models.\nLearn more about your ad choices. Visit podcastchoices.com/adchoices