Germany's Federal Motor Transport Authority (KBA) has been testing the Opel vehicles in recent months, according to a Bild on Sonntag report to be published in the Sunday newspaper.

According to the report, the KBA found indications that Opel has manipulated exhaust emissions in some diesel vehicles and that nitrogen oxide emissions were more than 10 times higher than permitted. 

Worldwide, about 60,000 cars are affected, including diesel versions of the Cascada, Insignia and Zafira models. Some 10,000 of the cars were made in Germany.

Current production of the cars is not affected, according to the report.

The KBA inspectors are reported to have found reliable information indicating that on some cars, for technically unexplained reasons, emissions control devices had been switched off while certain vehicles were driven.

Opel has two weeks to respond to the findings. An Opel spokesman on Friday evening said the carmaker could not comment on "open procedures which were started more than two years ago."

The KBA also made no comment on the newspaper's report. In a statement on Friday, the company said it had not received a notice from the KBA.

The automaker has been a subsidiary of French automaker Groupe PSA since August 2017. It had previously been owned by US automaker General Motors since 1929.

In its statement, Opel said: "We would like to remind you that Opel in December 2015 had already identified potential for improvement and started a technology initiative for more transparency, credibility and efficiency for the benefit of customers."

Dieselgate: a long-running scandal

Opel joining the ranks of other carmakers that have been accused of manipulating emissions levels in diesel cars. The scandal broke in 2015 when Volkswagen admitted it had installed illegal software in millions of diesel cars worldwide.

The software reduced nitrogen oxide emissions in standardized tests but not in normal operation on the roads. 

Many of the cases concerning the diesel scandal are continuing. Audi Chief Executive Officer Rupert Stadler was arrested in June as part of an investigation into suspected fraud and false advertising, and for an alleged role in helping to bring cars with illegal software to Europe.

In the United States, criminal charges were brought against VW former-CEO Martin Winterkorn over the emissions. He is unlikely to face charges because Germany does not extradite nationals to non-EU states. He resigned from his position at VW shortly after the Dieselgate scandal was made public.

Since 2015, VW has set aside $30 billion (€25.6 billion) to cover fines, vehicle refits and lawsuits.

jm/sms (AFP, dpa)

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