The BBC has reported that Mitsubishi Motors has admitted to falsifying some fuel consumption tests since 1991.
The company said that aggressive internal targets may have put pressure on employees to overstate the fuel economy of its vehicles.
Vice-President of Mitsubishi, Ryufo Nakao said:
"For the domestic market, we have been using that method since 1991". The number of models affected was not yet known, he added. "We don't know the whole picture and we are in the process of trying to determine that. I feel a great responsibility".
Mitsubishi logo, photo credit: Flickr.
Last week it was revealed that the company had falsified fuel economy data for more than 600,000 vehicles sold in Japan. This involved 157,000 of its eK wagon and eK Space vehicles, and 468,000 Dayz and DayzRoox vehicles produced for Nissan.
Mitsubishi has said there may be more models that have used tests that are non-compliant with Japanese standards, prompting concern about ballooning potential compensation costs and fines.
The company is in the process of an internal review from independent experts that is due to report in 3 months time.
Read more about emissions tests in our guide to cars
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