Volkswagen is in serious trouble. The automaker has admitted to using a device to cheat its way around the EPA testing that turned on during testing and off during normal driving. The four-cylinder TDI diesel engines sold in cars between 2009 and 2015 are affected, and this could mean that nearly 500,000 cars will be subject to recall here in the United States. Worldwide, 11 million vehicles are affected. It's been such a serious blow to the automaker that its stock has fallen massively.

Now the EPA is going to take a closer look at the automaker's 3.0-liter V-6 diesel, which is an engine found in plenty of Audi offerings and some Porsches as well.

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The 3.0-liter engine has already been certified by the EPA for the 2016 model year. That certification, however, came before the agency knew what they do about the 2.0-liter. This means there will be a much closer look of the 3.0-liter being undertaken. It's an incredibly important engine to Audi, as it is currently offered in the Q5, A6, A7 and the A8. Additionally, Porsche offers a TDI variant of the Cayenne with this engine here in the U.S., and the Panamera also offers it overseas.

We don't know yet if the 3.0-liter utilized the same software as the 2.0-liter. That engine is currently not being certified for the 2016 model year until Volkswagen can demonstrate that it properly meets U.S. emissions standards.

As it stands now, more countries are opening investigations into the TDI practices of Volkswagen. Criminal investigations are beginning as well. This is a massive problem for Volkswagen, a huge blow to all diesel sales in this country, and a potential problem for Porsche and Audi should those 3.0-liters come back screwy as well.


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