Japanese carmaker Mitsubishi Motors said on Tuesday that it did not comply with the country’s standards for fuel-economy testing on cars sold in Japan for 25 years.
The company said an external committee has been tasked with investigating what led employees to use improper testing methods and to overstate the fuel economy of Mitsubishi vehicles in data dating back to 1991, the Guardian reported.
The carmaker admitted last week that it had manipulated test results for four mini-vehicle models sold in Japan and said the cheating might also have extended to other models.
The company said there is no evidence of it has cheated fuel standards for vehicles sold overseas, including in the United States, the Guardian reported.
At a news conference on Tuesday, Mitsubishi President and COO Tetsuro Aikawa apologized to customers and said he had been “totally unaware” of the problem.
“I’m truly sorry that customers were led to buy vehicles based on incorrect fuel-efficiency ratings,” he said, according to the New York Times. “All I can do is apologize.”