Earlier this week, the Environmental Protection Agency issued the Volkswagen Group with a notice of violation for a 3.0-liter V-6 diesel engine used in several models from Audi as well as Porsche’s Cayenne and VW's Touareg. The violation was due to the discovery that several models fitted with the engine were found to have the same “defeat device” software used to hide emissions of harmful nitrogen oxide from regulators that VW previously admitted to using on roughly 11 million vehicles equipped with four-cylinder diesels.

VW has denied that the V-6 models also have the defeat device software but is going ahead with a stop-sale order until the situation can be fully investigated. The models originally listed by the EPA were the 2014 VW Touareg TDI, 2015 Porsche Cayenne Diesel and TDI versions of the 2016 Audi Q5, A6, A7 and A8.

According to The Detroit News, VW has gone a step further and issued stop-sale orders on even more models. A complete list of affected models can be found below:

Audi A6 TDI: 2014-2016
Audi A7 TDI: 2014-2016
Audi A8 TDI: 2014-2016
Audi Q5 TDI: 2014-2016
Audi Q7 TDI: 2013-2016
Porsche Cayenne Diesel: 2014-2016
Volkswagen Touareg TDI: 2013-2016

Unfortunately, VW’s troubles show no sign of abating. The automaker is still working on a fix for the 11 million cars already confirmed to have the defeat device software, and now there’s potentially hundreds of thousands or perhaps even millions of more vehicles affected. On top of all this, VW has discovered that around 800,000 of its cars had their CO2 levels—and thus fuel consumption figures—understated during CO2 certification.

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

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