Will Mitsubishi scandal scare off partners?

TOKYO -- Mitsubishi Motors Corp. is investigating whether vehicles exported to the U.S. are among those for which it falsified fuel economy tests to win better efficiency ratings.

Japanese media have reported that some Mitsubishi nameplates shipped overseas also may have manipulated test data, although the cheating scandal so far is isolated to the pint-sized minicars that are sold in Japan only.

But the scandal has larger implications for Mitsubishi. The misstep could serve as a red flag to other carmakers as Mitsubishi looks for global partnerships to flesh out its meager lineup.

The fake fuel economy results came to light only after partner Nissan Motor Co. noticed the discrepancies and called Mitsubishi out on it. The vehicles in question are minicars designed, manufactured and homologated by Mitsubishi and sold both as the Mitsubishi eK Wagon and eK Space and as the Nissan Dayz and Dayz Roox. 

"This is critical damage to the company and its ability to be a good corporate partner," Takaki Nakanishi, an auto analyst who runs his own research firm in Tokyo, said of Mitsubishi. "I don't think anybody really wants to deal with this company." 

Nissan said it has no plans "today" to change its relationship with Mitsubishi. Its first priority is finding a resolution for customers who bought the affected cars, the company said. 

The scandal added new tension to a not-always-smooth partnership between Mitsubishi and the Renault-Nissan Alliance.

Mitsubishi had been in talks with Renault to get a sedan to replace the Lancer or succeed the discontinued Galant. But those discussions fell apart. 

It then approached Nissan, but to no avail. In the end, Mitsubishi decided it would do without a midsize sedan, saying it will quit the segment. 

But corporate tie-ups are key to helping relatively small Mitsubishi flesh out its lineup and achieve bigger manufacturing scale. 

In Mexico, for instance, Mitsubishi supplies Fiat Chrysler Automobiles a rebadged version of its Attrage subcompact to sell as the Dodge Attitude. 

Mitsubishi also has been in talks with FCA about supplying the Fiat brand with a version of its Triton pickup, made in Thailand. 

If Mitsubishi's test fudging spills over to more vehicles, it could make other partners wary of collateral damage to their own brands, according to Nakanishi. "It is a mess," he said. 

According to a report in Japan's Sankei newspaper, Mitsubishi used the wrong testing methods on its i-MiEV electric car that is sold in the United States and possibly on two other models that are sold in the U.S. market -- the Outlander Sport compact crossover and Outlander midsize crossover.

On Wednesday, April 20, Mitsubishi President Tetsuro Aikawa called a snap press conference here to admit that his company had rigged fuel economy tests on some 625,000 minivehicles sold in Japan. 

They cover 157,000 units of the eK Wagon and eK Space and 468,000 units of Nissan's Dayz and Dayz Roox. 

Mitsubishi said it is checking whether it mishandled tests for other nameplates sold inside Japan or in other markets. It did not say how long the investigation would take. 

Mitsubishi also says it is discussing with Nissan how to compensate customers for the faked fuel economy numbers. 

Mitsubishi's engineers used a running-resistance value for fuel economy tests that gave better results than the cars should get. The running resistance value is a measure of the rolling resistance of tires and air resistance when a car is moving.