Volkswagen's use of emissions cheating devices on its larger 3.0 liter engine cars extends back five years earlier than originally reported, US regulators said Friday.

The Environmental Protection Agency said that officials from Volkswagen and its Audi unit had informed it that the devices covered all model years for the larger engines since 2009, just as long as the smaller 2.0 liter diesels -- the original source of the scandal over the "defeat devices."