By Amy Harder and Jason Chow, The Wall Street Journal.
U.S. regulators on Friday joined with governments in Europe and South America in pledging more emissions testing of diesel cars in real-world driving conditions, in the wake of revelations Volkswagen AG manipulated pollution checks.
The U.S. Environmental Protection Agency, in a letter to auto manufacturers, said it plans to road-test vehicles, rather than primarily rely on statements from auto makers and some laboratory testing. The agency also indicated it would check for the presence of software designed to trick emissions testing.
Its plans comes on the heels of similar pledges by European, Brazilian and other regulators this week to step up emissions testing or launched probes to determine whether there are widespread violations of exhaust-pollution rules in the auto industry.