WASHINGTON — Volkswagen’s emissions cheating scandal widened Friday after the U.S. Environmental Protection Agency said the German automaker used software to cheat on pollution tests on more six-cylinder diesel vehicles than originally thought.

Volkswagen told the EPA and the California Air Resources Board the software is on about 85,000 Volkswagen, Audi and Porsche vehicles with 3-liter engines going back to the 2009 model year. Earlier this month the regulators accused VW of installing the so-called “defeat device” software on about 10,000 cars from the 2014 through 2016 model years, in violation of the Clean Air Act.

The regulators said in a statement they will investigate and take appropriate action on the software, which they claim allowed the six-cylinder diesels to emit fewer pollutants during tests than in real-world driving.

The EPA said in a statement Friday night that VW had turned in its proposed fix, but the agency wouldn’t give details. The EPA will review the proposal, the statement said. VW said it is cooperating with regulators.