U.S. regulators have reportedly found three ‘unapproved’ software programs on VW’s Dieselgate-related V6 engines.

The report that originally came from the German newspaper Bild am Sonntag without naming a source said that the 3.0-litre V6 TDI diesel engine found in models like the original Audi Q7, the Porsche Cayenne and the VW Touareg has a software code that allows it to disable its emissions control systems after around 22 minutes. Official emission-measuring methods usually last 20 minutes, the report added.

Volkswagen has agreed to spend as much as $15.3 billion on buying back certain vehicles with 2.0-litre diesel engines from its U.S. customers. This agreement doesn’t include the around 85,000 models equipped with the rigged 3.0-litre TDI V6 engines, with a separate deal on them still months away.

Audi officials are going to appear at a hearing in front of U.S. authorities on August 10, with the company said to be expecting another hefty fine to be imposed on them.

Both the EPA and Audi declined to comment on the report, with Audi only saying that they are still in talks with U.S. authorities to agree to a technical solution for the problem.

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