EPA says Volkswagen cheated a second time on pollution tests

The U.S. government says Volkswagen cheated a second time on emissions tests, programming about 10,000 cars with larger diesel engines to emit fewer pollutants during testing than in real-world driving conditions.

The German automaker installed software designed to defeat the tests on about 10,000 vehicles from the 2014 to 2016 model years, according to the Environmental Protection Agency and California Air Resources Board. While on the road the cars give off up to nine times more nitrogen oxide pollution than allowed by EPA standards, the agency said.

Volkswagen previously acknowledged rigging emissions tests for four-cylinder diesel engines on 11 million cars worldwide, including almost 500,000 in the U.S.

The EPA says the software on the six-cylinder diesels has a timer that turns on pollution controls when testing begins, including fuel injection timing, exhaust gas recirculation rate and fuel injection pressure. All cause the cars to emit less nitrogen oxide pollution by operating at high exhaust temperatures, the agency says in documents posted Monday. One second after the first phase of the test ends, the cars return to normal operation.

The violations cover models including the 2014 Touareg, 2015 Porsche Cayenne and the 2016 Audi A6 Quattro, A7 Quattro, A8 and Q5.

Volkswagen faces fines of up to $37,500 per vehicle, which means up to $375 million could be added to penalties already projected in the billions of dollars.

"VW has once again failed its obligation to comply with the law that protects air quality for all Americans," said Cynthia Giles, assistant EPA administrator.

The Associated Press