Concerns were raised by employees as long ago as 2005.

Mitsubishi ignored pleas from its own employees to stop cheating fuel economy tests as long ago as 2005, an investigative committee has said.

In April the Japanese automaker admitted rigging fuel economy tests on its own eK Wagon and eK Space mini-cars, plus the near-identical Dayz and Dayz Roox models it builds for Nissan.

Mitsubishi’s own investigations found that irregularities in fuel economy testing had existed since 1991, and that every model it has built and sold over the last decade is affected.

The new revelations come from a special investigative committee set up by Mitsubishi, comprising lawyers and experts from outside the company. Its report, published on August 2, says that in 2005 a new employee raised concerns about fuel economy testing procedures at a company workshop, having noticed differences from government-approved methods.

The employee, identified only as ‘F’, pleaded for the practice to stop. Current CEO Osamu Masuko had started in his job only a month before.

Further, responses to a company questionnaire circulated in 2011 also raised concerns about fuel economy tests, but management accepted a report from the development department that asserted: “There is no problem.”

Speaking at a news conference after the committee’s report was published, Masuko said that Mitsubishi’s own investigations had highlighted neither the new employee’s concerns, or those raised in response to the questionnaire.

He added: “We lacked unity to detect problems within the company and to solve them. From now on, we need to decide how to change our way of thinking.”


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