Porsche is under investigation by the German Federal Motor Transport Authority (KBA, or Kraftfahrt-Bundesamt) according to the German magazine Wirtschaftswoche, following a similar analysis that found fellow Volkswagen Group brand Audi using unauthorized software for emission testing.
The Audi software runs in a cheat mode based on steering angle. When steering angle does not exceed 15 degrees, the engine computer recognizes that the vehicle is on a test bench and emits pollutants at a level that does not reflect the vehicle?s real-world performance. Above that 15 degree threshold, certain Audi A7s and A8s were found to emit significantly higher levels of nitrogen oxide than previously reported. German Transport Minister Alexander Dobrindt considers this sort of cheat software misleading and illegal, and he has forced Audi to recall 24,000 of the large sedans.

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The KBA is investigating whether Porsche used similar software, although the automaker is denying all allegations. A Porsche representative stated via email that Porsche is not using steering movements to detect a test bench in any of its vehicles.

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