TOKYO — Japan's Mitsubishi Motors Corp. said Wednesday it found evidence its workers falsified fuel economy test data for several models of vehicles.
The Tokyo-based automaker said the inaccurate tests involved 157,000 of its own-brand eK wagon and eK Space light passenger cars, and 468,000 Dayz Roox vehicles produced for Nissan Motor Co.
The problem was found after Nissan pointed out inconsistencies in data, the company said. Mitsubishi conducted an internal probe and found that tire pressure data was falsified to make mileage appear better than it actually was.
It is the first time a Japanese automaker has reported misconduct involving fuel economy tests since Volkswagen last year was discovered to have cheated diesel emissions tests in the United States and elsewhere.
Mitsubishi said it would investigate whether data were altered for vehicles sold overseas.
It said it would stop making and selling the affected cars, and has set up an independent panel to investigate the issue.
The company, Japan's sixth-largest automaker, struggled for years to win back consumer trust after an auto defects scandal in the early 2000s over cover-ups of problems such as failing brakes, faulty clutches and fuel tanks prone to falling off dating back to the 1970s.
In Japan, shares in Mitsubishi closed down more than 15 percent at 733 yen each, the stock's biggest one-day drop in almost 12 years.