The Volkswagen Group, still reeling from an announcement Monday made by the Environmental Protection Agency that more of its cars, including some Porsches and high-end Audis, were fitted with “defeat device” software used to hide emissions of harmful nitrogen oxide from regulators, has now discovered irregularities in CO2 levels of some of its cars.

According to the German automaker, around 800,000 cars could be affected, potentially leading to economic risks totaling as much as 2 billion euros (approximately $2.2 billion). VW states that the CO2 levels—and thus the fuel consumption figures—for the affected cars were understated during the CO2 certification process.

The automaker hasn’t revealed what models are affected, as a reliable assessment of the scale of the issue is yet to be determined. The automaker does, however, state that most of the vehicles are fitted with diesel engines, meaning some gasoline models are likely to be counted. It’s understood that this latest issue is unrelated to vehicles sold in the United States, though.

VW is cooperating with regulators to address the issue and says it will do everything in its power to clarify the further course of action as quickly as possible and ensure the correct CO2 classification for the vehicles affected. We have to wonder, though, as VW continues its review of tailpipe emissions of the millions of cars it sells around the world each year, how many more are potentially on the wrong side of regulations.

VW’s emissions cheating scandal first emerged in September when the EPA announced that a number of the automaker’s diesel-powered cars were discovered with the defeat device software. The software was said to be able to detect when an official emissions test was being run and in such a case turn on full emissions control systems. During normal driving conditions, these control systems were switched off, providing the cars with better performance though with emissions such as nitrogen oxide (NOx) sometimes as much as 40 times higher than standards allow.

VW determined that around 11 million vehicle were affected worldwide, with 482,000 of them in the U.S. The automaker has since attempted to discover how the situation came to be, who was responsible and how the cars can be fixed. The first recalls for this original issue is expected to commence in January 2016.

The scandal took a new turn this week when the EPA discovered more cars fitted with the defeat device software, and now VW also has the CO2 irregularities to deal with.

To keep track of our past coverage on VW's emissions cheating scandal, head to our Volkswagen news hub.


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