Detroit - There's a new twist to the so-called Dieselgate scandal after the US Environmental Protection Agency on Thursday accused Fiat Chrysler of illegally using hidden software to allow excess diesel emissions to go undetected, the result of a probe that stemmed from regulators' investigation of Volkswagen.
The EPA action affects 104 000 US diesel-powered Jeep Grand Cherokee SUVs and Ram pick-up trucks sold since 2014, about one-sixth the vehicles in the Volkswagen case.
The EPA and California Air Resources Board told Fiat Chrysler it believes its undeclared auxiliary emissions control software allowed vehicles to generate excess pollution in violation of the law and each issued notices of violation.
Fiat Chrysler Chief Executive Sergio Marchionne angrily rejected the allegations at a hastily-assembled conference call with reporters, saying there was no wrongdoing and the company never attempted to create software to cheat emissions rules by detecting when the vehicle was in test mode.
He characterised the dispute as whether the carmaker had completely disclosed software that protects the engine, adding that the company was planning updated software to address EPA concerns.
He said the EPA and the company could have settled the issue in "a more efficient way" without the EPA announcement, and he said "I'm really pissed off" about reports that equate FCA's issues with VW's.
"The way that it has been described, I think, has been unfair to FCA, and that is the thing that disturbs me most," Marchionne said.
He also suggested regulators had a "belligerent" view of carmakers. "We don't belong to a class of criminals," he said. "We're not trying to break the bloody law."
The company has no plans to stop selling 2016 US diesel models.
The EPA has is busy reviewing other carmakers' emissions systems, but it is not clear if they have found any additional wrongdoing.
Cynthia Giles, an EPA official, said Fiat Chrysler had an obligation to disclose the "illegal software" but has not decided whether to label them "defeat devices."
The EPA said it found at least eight undisclosed pieces of software that can alter how a vehicle emits air pollution. Fiat Chrysler had recalled vehicles for one of the undisclosed software.
By contesting the charge, FCA will push the case into the administration of President-elect Donald Trump. It is not clear how Trump's EPA will handle this or similar issues. Trump has nominated Oklahoma Attorney General Scott Pruitt, a critic of federal environmental regulation, to lead EPA.
Efraim Levy, analyst with CFRA, said FCA stands to "get a fresh start with the Trump administration."