General Motors’ Opel division is being asked for more details concerning diesel engines that can disable pollution controls under specific circumstances. This request is coming from a German government commission that wants further explanation on the matter.

Opel representatives appeared before the government panel after a report that Zafira automobile can reduce pollution controls at some speeds and temperatures. The charges were reported by the German environmental group DUH and reported in the German weekly news source, Der Spiegel. Opel has been ordered to submit technical details regarding engine emission controls that are reduced above 145 kph (90mph) and below a specified air pressure.

Opel claims the reductions are necessary to protect the engine, a claim the panel.Opel must submit technical details within two weeks. German Transport Minister Alexander Dobrindt stated, “Opel stressed to us that they are within the framework of the law with the measures they described,” Dobrindt said. “On two points, we told the Opel representatives that we have doubts as to whether these measures fully serve in protecting the engine.”

Opel claims they are operating within regulation and denies doing anything illegal. Opel CEO Karl-Thomas Neumann said that Opel uses no illegal engine control software and will cooperate fully with the commission and their examination. Could this be the next dieselgate to hit the diesel market?