Mitsubishi Motors has admitted it has been using unorthodox fuel economy testing methods in Japan for the last quarter of a century.

The shocking announcement was made today, almost one week after Japan’s sixth-largest car manufacturer revealed it has been falsifying fuel economy test data. According to Reuters, the company has lost half of its market value since the original announcement and you can imagine this new piece of information will further affect the company’s finance.

In a previous statement, Mitsubishi admitted the oldest non-compliance concerning fuel economy dated back to at least 2002. However, now Mitsu is saying it has been using testing methods that do not comply with the Japanese regulations since 1991.

Rather than using the testing methods applicable in its domestic market, Mitsubishi performed the fuel economy tests using U.S. standards. The difference between the two is quite significant, as while the one in Japan focuses more on city driving, the U.S. tests put a greater emphasis on highway driving. Needless to say, fuel consumption is higher in a city’s stop and go traffic compared to driving on the highway at steadier speeds.

To try and escape from this ordeal as soon as possible, Mitsubishi has set up a special investigation committee consisting only of external experts. For the next three months, these people will be in charge of analyzing the company’s lengthy improper conduct and uncover the cold hard facts.

Source: Mitsubishi via Reuters

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