The VW emissions scandal investigation is examining revelations that petrol cars produced by the group are now also included in false emissions reporting. Volkswagen, Audi and Porsche cars are reportedly involved.
The biggest German Sunday newspaper, Bild Am Sonntag, says Volkswagen engineers have told investigators that certain petrol engines in VW, Audi and Porsche vehicles can be used to manipulate emissions tests.
A spokesman for Volkswagen - the parent company of Audi and Porsche - told Reuters that VW would not comment on an ongoing investigation, adding that the company in recent months had held intensive talks with the Federal Motor Transport Authority.
"There are no new circumstances here," he said.
Gearboxes and software could be manipulated so that vehicles show lower levels of carbon dioxide (CO2) emissions and fuel consumption, Bild said, citing internal documents and witnesses statements.
VW’s emissions scandal has cost the carmaker 27 billion euros in penalties and fines for systematic manipulation of diesel-powered cars to mask excessive pollution levels.
In Europe, vehicles are taxed according to their levels of polluting CO2 emissions.
Reuters said It remained unclear whether the Bild documents represent a new dimension to the Volkswagen cheating scandal since the carmaker in 2015 admitted that around 36,000 petrol-fueled cars were also being tested for excessive emissions.
VW had the 36,000 cars checked by a neutral body under supervision by the regulator and found minimal deviation from requirements. The automaker was not required to make any technical changes to those vehicles.
Regulators in the United States blew the whistle on deliberate emissions cheating three years ago after it emerged that the carmaker had developed an engine that failed to conform to pollution standards.
VW used software to detect when a car was being subjected to a regulatory emissions measurement test, and throttled back the engines during the test cycle, masking excessive pollution.
When a car engine was being accelerated and gears changed, VW’s onboard software would check whether the steering wheel was also being used. If the steering wheel angle was not being altered, VW knew a vehicle was strapped to a dynamometer test bench, activating exhaust emission filters.
