Germany's Volkswagen, already reeling from the fallout of cheating on US emissions tests for nitrogen oxide, said Tuesday that an internal investigation has revealed "unexplained inconsistencies" in the carbon dioxide emissions from 800,000 of its vehicles—a development it said could cost the company another $2.2 billion. The investigation was undertaken by the company after a string of problems identified with Volkswagen emissions, which have caused share prices to plummet. In September, the company admitted it had installed software designed to defeat tests for nitrogen oxide emissions for four-cylinder diesel engines on 11 million cars worldwide, including almost 500,000 in the US. It has already set aside $7.4 billion to cover the costs of recalling those vehicles—and analysts expect the emissions scandal to cost the company much more than that.
That scandal had already widened this week, when the US Environmental Protection Agency said Volkswagen had installed software on thousands of Audi, Porsche, and VW cars with six-cylinder diesel engines that allowed them to emit fewer pollutants during tests than in real-world driving. Volkswagen has denied the charge, but faces the prospect of more fines and lost sales. It was not immediately clear whether the 800,000 vehicles announced Tuesday with the newly discovered carbon dioxide emission problems were among those already affected. Volkswagen did not identify any models by name. It did say the 800,000 were "predominantly vehicles with diesel engines," raising the possibility for the first time that some Volkswagens with gasoline-powered motors may also have emissions problems. CEO Matthias Mueller promised Tuesday that Volkswagen "will relentlessly and completely clarify what has happened." (Read more Volkswagen stories.)