The U.S. Environmental Protection Agency accused Volkswagen AG VLKAY -4.52 % of deliberately dodging air-pollution rules on nearly half a million cars sold, furthering an Obama administration crackdown on auto makers for flouting regulations intended to reduce tailpipe emissions. The EPA, which unveiled the allegations with the California Air Resources Board, issued a notice on Friday alleging the German auto maker used software in the cars to get around government emissions tests. EPA officials said the software, dubbed a “defeat device,” worked to make 482,000 Volkswagen cars appear cleaner than they were. The Clean Air Act requires vehicle manufacturers to certify to EPA that their products meet federal air-pollution standards. EPA officials said Volkswagen violated two parts of the federal Clean Air Act and could face sizable financial penalties of up to $37,500 per car, or more than $18 billion. But it remained unclear whether the government would seek […]