(CN) - Nearly 600,000 diesel-engine vehicles made by Volkswagen, Porsche and Audi had illegal devices to defeat emissions testing, the U.S. government claims in a federal complaint filed Monday.
The 29-page complaint filed in Detroit comes nearly three months after the U.S Environmental Agency forced a recall of cars that it found had been outfitted with "defeat-device" software that had been hoodwinking emissions inspectors for years.
Using a sophisticated algorithm, the software kicks into full emissions-control mode only when it detects the vehicle is undergoing inspections.
While the cars meet standards under laboratory settings, they spew nitrogen oxides at up to 40 times that limit on the road, the EPA said.
Nitrogen oxide pollution has been linked to increased asthma attacks and deadly respiratory and cardiovascular illnesses.
The scandal led to the resignation of CEO Martin Winterkorn, hundreds of federal class actions recently consolidated in San Francisco, plus multiple investigations and congressional hearings.
Two months after the EPA flagged VW's 2-liter engine vehicles since 2009, regulators announced that Porsches and Audis fitted with 3-liter engines also incorporated the so-called defeat-device software. Also in November, VW divulged "unexplained inconsistencies" in the carbon dioxide emissions from 800,000 of its vehicles.
The government's new lawsuit accuses Volkswagen of violating the Clean Air Act by not fulfilling the applications for certification it submitted to the EPA and the California Air Resources Board (CARB).
Volkswagen said in a statement that it "will continue to work cooperatively with the EPA on developing remedies to bring the TDI vehicles into full compliance with regulations as soon as possible."
TDI is an abbreviation for turbocharged direct injection, Volkswagen's diesel engine design.
Volkswagen also said it is working to develop an independent, fair and swift process for resolving private consumer claims relating to these issues.
Though regulators have been working with Volkswagen on a massive recall, negotiations so far have "not produced an acceptable way forward," said Cynthia Giles, assistant administrator for enforcement and compliance assurance at EPA.
Negotiations "will continue in parallel with the federal court action," Giles added.
The government is seeking up to $2,750 for each defeat device before Jan. 13, 2009, and up to $3,750 for each defeat device after Jan. 13, 2009.
Volkswagen also faces up to $37,500 per day of violations of the Clean Air Act, which could cost the automaker billions of dollars.
With regard to 2-liter engines, the complaint covers approximately 499,000 diesel vehicles that VW sold in the United States since the 2009 model year.
The government says it also covers approximately 85,000 diesel vehicles with 3-liter engines that VW sold in the United States in the same time frame.
A list of the affected cars and model years is included in an appendix with the complaint.
The 2-liter engines are found in Jettas from 2009 to 2015; Jetta Sportwagens from 2009 to 2014; Beetles and Beetle convertibles from 2013 to 2015; Audi A3 from 2010 to 2015; Golfs from the same time period, Golf Sportwagens just from 2015; and Passats from 2012 to 2015.
The affected 3-liter models are Volkswagen Touaregs from 2009 to 2016; Porsche Cayenne from 2013 to 2016; and six models of Audis. From 2014 to 2016, the models are Audi A6 Quattro, Audi A7 Quattro, Audi A8, Audi A8L and Audi Q5.
Audi Q7s from 2009 to 2015 are the final model affected.
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