WASHINGTON (Reuters) - Fiat Chrysler Automobiles NV (>> Fiat Chrysler Automobiles NV) plans to update software that it expects will resolve the concerns of U.S. regulators about excess emissions in 104,000 older diesels, the Italian-American automaker said on Friday.

The company also said on Friday that it had formally sought approval to sell two 2017 diesel models after months of talks and testing.

The software update would begin rolling out once the Environmental Protection Agency and California Air Resources Board approved, Fiat Chrysler said. The company said it does not anticipate any impact on performance or fuel efficiency.

The EPA declined to comment. California said in a statement it "is continuing its discussions with FCA to fully address and resolve the issues" it raised.

In January, the EPA and California accused Fiat Chrysler of illegally using undisclosed software to allow excess diesel emissions in 104,000 U.S. 2014-2016 Jeep Grand Cherokees and Dodge Ram 1500 trucks in a notice of violation.

The notice was the result of a probe that arose out of regulators' investigation of rival Volkswagen AG's (VOWG_p.DE) excess emissions.

Reuters reported on Wednesday that the Justice Department is preparing to file a civil lawsuit against the automaker for selling 104,000 vehicles that emit excess diesel emissions if it does not reach an agreement with the company.

Fiat Chrysler said Friday it believes "these actions should help facilitate a prompt resolution to ongoing discussions with the Environment and Natural Resources Division of the U.S. Department of Justice and other governmental agencies."

Fiat Chrysler shares rose as much as 4.3 percent in Friday trading on the New York Stock Exchange, but ended virtually unchanged from Thursday's close.

The vehicles' engines were manufactured by VM Motori SpA, a subsidiary of FCA, and some component parts for the engines were supplied by Robert Bosch GmbH.

Bosch faces about two dozen lawsuits from owners over the FCA diesel vehicles.

The Justice Department and the EPA have obtained internal emails and other documents written in Italian that look at engine development and emissions issues that raise significant questions, Reuters reported Thursday.

A federal judge in California set a May 24 hearing on a series of lawsuits filed by owners of vehicles and some dealers against Fiat Chrysler and the Justice Department is expected to file its action by then if no agreement is reached.

(Reporting by David Shepardson; editing by Grant McCool)

By David Shepardson

Stocks treated in this article : Volkswagen AG, Fiat Chrysler Automobiles NV