In April, Mitsubishi Motors Corporation (MMC) admitted to manipulating fuel consumption testing data for some 625,000 mini-cars representing four models it manufactured for sale in Japan by itself and partner Nissan. (Earlier post.)
MMC now says that its internal hearings into the cheating suggest that the method used to cheat—the improper calculation of running resistance—was also applied in nine other models currently sold in Japan, as well as in other models no longer sold in Japan. The use of the calculations is also suspected on the RVR and some other models, and investigations into the background and details are ongoing and will be announced separately.
The findings came in a report submitted by Mitsubishi Motors Corporation (MMC) to the Ministry of Land, Infrastructure, Transport and Tourism (MLIT) today, pursuant to instructions received from MLIT on 20 April to investigate improper conduct in fuel consumption testing of vehicles manufactured by MMC.
The investigation found that the improper manipulation of running resistance to present better fuel consumption rates began with the development of the fuel-economy grade for the model year 2014 eK Wagon and Dayz (Application for the certifications submitted February 2013). Running resistance for other grades (standard grade, turbo grade, 4WD grade) as well as for the eK Space and Dayz Roox and each model year change were simulated using testing data from the fuel-economy grade vehicles.
During the development of the fuel-economy grade, the fuel consumption target was raised a total of five times, from 26.4 km/L (62 mpg) to 29.2 km/L (68.6 mpg). Development progressed based on an overly optimistic outlook because of deep concern regarding new competitor fuel consumption levels, even though realistic attainment of the targets was problematic, MMC’s report said.
The coordinators at the time were well aware that fuel consumption meant “the factor that would give the most product marketing appeal”—so they felt that the fuel consumption improvement targets requested by managers and executives were absolute.
Administrative managers in development-related departments did not communicate well enough with the subcontractor so did not confirm the real situation, even though they understood the problematically high fuel consumption targets.
MMC said that it is considering “drastic reforms” in order to prevent recurrence.
On 25 April, MMC established a Special Investigation Committee consisting entirely of outside experts was established to investigate this matter more thoroughly, including the reasons for and details behind MMC’s use of the high-speed coasting test. After receiving the Committee’s advice and recommendations MMC will devise new measures and will submit a separate report.