A total of 3.3 million Audi and Skoda cars fitted with the software that allowed parent company Volkswagen to cheat US emissions tests, the automakers say.
Some 2.1 million Audi vehicles affected worldwide include 1.42 million in western Europe, with 577,000 in Germany, and almost 13,000 in the US.
Meanwhile, German prosecutors started a probe against VW’s former boss, Martin Winterkorn.
Martin Winterkorn will be investigated over “allegations of fraud in the sale of cars with manipulated emissions data,” German authorities said on September 28.
The Audi models affected include the A1, A3, A4, A5, A6, TT, Q3 and Q5 models, a spokesman told the Reuters news agency.
VW said last week that 11 million cars within the group could be affected.
The scandal was revealed after the US Environmental Protection Agency (EPA) found that some diesel cars were fitted with devices that could detect when the engine was being tested and could change the car’s performance to improve results.