VW chief knew about possible US probe over emissions

Former Volkswagen (VW) CEO Martin Winterkorn had learned as early as May 2014 that the US authorities would probably inspect the company's cars for an emissions cheating, German newspaper Bild am Sonntag reported.

A VW employee wrote to Winterkorn that the car maker had failed to provide an explanation for elevated nitrogen oxide emissions and that the authorities would conduct checks for a test-recognition function in motor-steering software, according to the newspaper, which cited a company document. The employee was not identified by it.

According to VW's admission last September it had rigged some diesel engines to ensure emissions controls came on only during testing.

When the vehicles were on the road, the engines emitted nitrogen oxide much in excess of the US legal standard. Europe's largest vehicle manufacturer could be penalised billions of dollars.

According to Eric Felber, a VW spokesman, the  company's investigation into the matter would be concluded in the second half of April.

Meanwhile, Bild cited German transport minister Alexander Dobrindt as saying VW needed to win back trust globally.

"It's important that those responsible be clearly named and made accountable," the minister was quoted as saying in an interview, without referring to Winterkorn. Dobrindt added that unannounced emissions tests would be carried out on all car manufacturers.

Volkswagen admitted in September 2015 to cheating in pollution tests but had maintained that only a small number of employees were to blame and there was no evidence of the involvement of board members.