Automaker Nissan announced the sample testing at its Japanese factories failed to meet national testing standards, leading to improper measuring of exhaust emissions and fuel economy.
According to reports, the incident marks the second time this year the company has reported issues with its inspection process. In addition to the emissions and fuel economy tests, Nissan said tests for external vehicle noise, horn volume and headlights were also conducted improperly.
Related: GM Issues Recall on 2015 Trucks, SUVs
The automaker blamed a lack of oversight by its plant managers and a shortage of inspectors, as well as a need for more training. It plans to have future tests overseen by supervisors and increase its number of inspectors going forward.
The questionable testing only impacted vehicles that were to be sold in Japan. None of the cars in question were exported for sale in other countries.
