Volkswagen produced hundreds of thousands of cars with a device made to intentionally evade air pollution standards, according to a citation issued today by the Environmental Protection Agency.
The EPA alleges that nearly 500,000 VW cars sold in the United States over the last several years were equipped with the device, which the EPA says enabled the onboard computer to detect when the car was undergoing an emissions test. At that time, the engine would operate in a way that complied with emissions standards; at all other times, the car would produce emissions of harmful gases up to 40 times greater than allowed by federal law. The primary gas in question is nitrogen oxide, which causes smog, which is a leading cause of respiratory ailments.
This table from the citation lists the models that were allegedly outfitted with the illegal device. All of the cars in question had diesel engines:
The EPA cites a 2014 study by the International Council on Clean Transportation that found a troubling gap between real-world and laboratory emissions in some diesel cars, without naming specific manufacturers.
“When you test it in the lab, they looked great,” said Anup Bandivadekar, one of the study’s authors. “But when you actually drive them around, emissions were much higher.”
The citation issued today lifted the curtain on the specific cars in question and delineates the federal laws VW is accused of violating. The EPA is continuing to investigate the charges and has passed the citation to the Justice Department, where it will be up to federal prosecutors to prove the charges. Volkswagen could be compelled to fix all the cars and pay up to $3,750 per car (roughly $18 billion altogether) in fines.
In a statement, a Volkswagen spokesperson said the company was cooperating with the investigation but declined to comment further.