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Mitsubishi fuel economy tests have been incorrect since 1991 – report

Mitsubishi logoMitsubishi fuel economy test procedures have not been compliant with Japanese regulations since 1991, an unnamed source has revealed.

Reuters says the leaked news was first reported to Japanese business title Nikkei: Mitsubishi is to hold a press conference briefing on the matter later today.

It is said the firm compiled its fuel economy data using U.S. standards, which involves more high-speed driving, rather than Japanese standards which demand more stop-start inner-city driving. Japanese standards generally deliver worse economy figures than U.S. standards.

The latest Mitsubishi revelation follows last week’s admission that it overstated the fuel economy of four city cars, sold under both the Mitsubishi and Nissan brands.

Since then, the firm – Japan’s sixth-largest vehicle manufacturer – has lost half its market value.

Manipulation of fuel-efficiency tests is “extremely serious,” Japanese transport minister Keiichi Ishii told reporters yesterday after a cabinet meeting, reports Bloomberg.

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