Mitsubishi Motors Corporation (MMC) admitted to falsifying fuel consumption tests for several of their vehicles. They admitted to manipulating fuel economy data for four mini-car models: two for their own brand (eK Wagon, ek Space) and two produced for Nissan Motor (Dayz, Dayz Roox). In a press release, the Japanese automaker apologized and owned up to the outrage.

"In connection with the certification process for the mini-cars manufactured by MMC, we found that with respect to the fuel consumption testing data submitted to the Ministry of Land, Infrastructure, Transport and Tourism (MLIT), MMC conducted testing improperly to present better fuel consumption rates than the actual rates; and that the testing method was also different from the one required by Japanese law. We express deep apologies to all of our customers and stakeholders for this issue," their official statement read.

The official statement also revealed that it was Nissan who noticed the irregularity of the data and who initiated to conduct in-house testers. After the internal probe, it was ascertained that there was an obvious incongruity between the cars' promised fuel efficiency data, and the actual results. The Sydney Morning Herald reported that inaccurate tests involved 157,000 of its own brand light passenger cars and 468,000 vehicles of the latter. 

"Nissan Motor (NM) requested Mitsubishi Materials Corporation (MMC) to review the running resistance value set by MMC during tests by MMC. In the course of our internal investigation upon this request, MMC learned of the improper conduct that MMC used the running resistance value for testing which provided more advantageous fuel consumption rates than the actual rates," announced Mitsubishi. The data was said to be manipulated to make fuel economy performance appear more efficient.

"The wrongdoing was intentional. It is clear the falsification was done to make the mileage look better. But why they would resort to fraud to do this is still unclear," company president Tetsuro Aikawa told the Associated Press. After the news broke, shares in Mitsubishi declined more than 15 percent, "slashing off $1.2 billion from the company's market value," The Verge notes.