Volkswagen Software Cheated Emissions Test: EPA

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The US Environmental Protection Agency on Friday charged Volkswagen with deliberately employing software designed to bypass emission standards in almost half a million cars and ordered the company to fix its non-compliant vehicles.

The EPA issued a notice of violation (NOV) of the Clean Air Act to Volkswagen AG and its subsidiaries, Audi AG and Volkswagen Group of America. The NOV claims that four-cylinder Volkswagen and Audi diesel cars from model years 2009-2015 used a "defeat device" that regulates emissions only during emissions testing.

According to tests conducted by the EPA and the California Air Resources Board (CARB), affected vehicles emit as much as 40 times more pollution than allowed by emission standards.

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"VW is cooperating with the investigation; we are unable to comment further at this time," Volkswagen said in an emailed statement.

In a blog post, environmental advocacy group Clean Air Watch said the EPA's charges are "truly appalling."

The CARB, in a separately issued compliance violation letter, stated that Volkswagen officials acknowledged the deception was deliberate. "During a meeting on September 3, 2015, VW admitted to CARB and EPA staff that these vehicles were designed and manufactured with a defeat device to bypass, defeat, or render inoperative elements of the vehicles' emission control system," the letter said.

The EPA in its NOV alleged, "...VW manufactured and installed software in the electronic control module (ECM) of these vehicles that sensed when the vehicle was being tested for compliance with EPA emissions standards."

During tests, the software produced compliant emissions results. But on the road, the software allowed NOx emissions ranging from 10 to 40 times higher than EPA limits, depending whether the vehicle was driving in a city setting or on a highway.

The issue came to light in May 2014 when West Virginia University's Center for Alternative Fuels, Engines, and Emissions conducted a study commissioned by International Council on Clean Transportation. WVU tested a 2012 VW Jetta and a 2013 VW Passat. The emissions data found by WVU researchers differed from that reported by VW.

After a voluntary recall in December 2014 showed only minor improvement, CARB broadened its testing to understand the results it was getting. According to the EPA, it was only after CARB and the EPA refused approve VW's 2016 diesel vehicles that the carmaker admitted it had installed a bypass device.

The following VW and Audi model years are affected: Jetta (2009–2015), Beetle (2009–2015), Audi A3 (2009–2015), Golf (2009–2015), and Passat (MY 2014-2015). VW is required to cover the cost of compliance. The company has not issued a recall notice. In its statement, the company said owners of affected cars do not need to take any action at this time. 

VW faces fines of up to $37,500 per vehicle, or more than $18 billion for 482,000 affected vehicles, as well as additional fines. The EPA has not yet specified the total penalty it will seek.