Germany wants stricter European Union rules on emissions from motor vehicles, the transport ministry said on Monday, confirming a report by the financial daily Handelsblatt.
The proposal came after a German investigative committee last month listed 30 car models that showed suspiciously high levels of CO2 emissions and would require further testing.
Germany subjected diesel models to tests after Volkswagen admitted it had cheated U.S. emissions tests by installing software capable of deceiving regulators in up to 11 million diesel vehicles worldwide.
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The Handelsblatt report of a German call for tougher rules cited a document prepared for a meeting of EU transport ministers in Luxembourg on Tuesday.
The thrust of the proposal appeared to be to toughen CO2 rules enough to help defeat or deter the use of technology in car engines that can outwit emissions tests.
The document also said carmakers should be forced to disclose what kind of technology they use to protect engines in punishing driving conditions and how such software works.
Transport Minister Alexander Dobrindt said last month that General Motors’ Opel division had admitted that its Zafira model includes engine software that switches off exhaust treatment systems under certain speed and air pressure conditions in order to protect the engine. But Opel said such technology was legal.
The case is distinct from the emissions case involving Volkswagen, which concerned the rigging of exhaust emissions tests as opposed to shutting down exhaust reduction systems under certain conditions.