According to a report by Bloomberg, Fiat Chrysler Automobiles NV is under investigation by the Department of Justice for a possible violation of the Clean Air Act. Bloomberg's report cites "people familiar with the investigation."

As we learned yesterday, the EPA is accusing FCA of failing to disclose engine management software for its 3.0-liter V-6 turbodiesel engine that could cause the engine to emit nitrogen oxide, or NOx, in excess of the standard, thus violating the Clean Air Act. Thus far the EPA has only issued a Notice of Violation challenged FCA to show least eight auxiliary emission control devices aren't defeat devices.

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FCA CEO Sergio Marchionne says his company's engine management software is not like Volkswagen's "defeat devices."

"They cannot be classified as defeat devices because we're trying to defeat nothing," he said yesterday. "These were mechanisms that were put in place to protect the engine in particular circumstances when the engine was under load."

The issue involves some 104,000 2014-2016 Ram 1500s and Jeep Grand Cherokees equipped with a 3.0-liter turbodiesel V-6 engine. The California Air Resources Board (CARB) has also released a notice of violation.

The EPA says owners of these vehicles can continue to drive them.

The Securities and Exchange Commission and the DOJ are already looking into FCA for its sales reporting practices.

If found in violation of the Clean Air Act, FCA could be fined up to $44,539 per vehicle, though the fines would likely be much less. The DOJ could levy further fines and pursue criminal charges against individuals.