NEW YORK/DETROIT (Reuters) - The U.S. Environmental Protection Agency on Thursday accused Fiat Chrysler Automobiles NV of illegally using hidden software to allow excess diesel emissions to go undetected, the result of a probe that stemmed from regulators' investigation of rival Volkswagen AG.
FCA shares plummeted as the maximum fine is about $4.6 billion. The EPA action affects 104,000 U.S. trucks and SUVs 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.
The U.S. Justice Department is investigating, Fiat Chrysler said Thursday. New York Attorney General Eric Schneiderman said in a statement he is "deeply troubled" by the EPA findings and "will investigate the claims against Fiat Chrysler and stands ready to work with our state and federal partners."
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 characterized the dispute as whether the automaker had completely disclosed software that protects the engine, adding 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.