IHI admits improper alteration of data over 4,000 marine engines

Japanese engine maker IHI Corporation is being investigated by authorities after the company admitted to falsifying fuel efficiency data for more than 4,000 engines going back 20 years.

The company now reports it was able to confirm widespread efforts to alter fuel efficiency results from “test run records of marine engines and land engines manufactured and sold by our company,” according to a statement on IHI Power Systems website.

Data-rigging was found at IHI Power Systems Co’s plants in Niigata and Gunma prefectures, with data doctored during tests to make their fuel economy look better.

In all, IHI said the manipulated data affects about 4,361 (or 81% of the 5,337 engines shipped from the two plants) engines produced at least since 2003, for the domestic and overseas markets.

The engines are mostly for ships (including Japanese Coast Guard vessels), but also extend to engines produced for land-based applications such as trains.

On 25 April, inspectors from Japan’s Ministry of Land, Infrastructure, Transport and Tourism conducted raids at the Niigata and Gunma manufacturing plants.

The subsidiary’s in-house investigation showed some products could be in violation of nitrogen oxide emissions regulations stipulated by Japan’s Marine Pollution Prevention Law and International Maritime Organisation (IMO) regulations.

Japan’s Asahi Shimbun newspaper reported that IHI’s in-house investigation suggested falsifications may have stretched back to the 1980s. 

The company has issued a formal apology and said it sincerely regretted the betrayal of trust.

Authorities are reportedly collecting information and interviewing personnel at IHI. An employee also told investigators that all workers engaged in engine test runs were aware that data has been falsified, according to reports attributed to Japanese officials.

IHI Corporation said 2,058 engines did not meet specifications set under contracts with its customers.

The Transport Ministry has now called on IHI and its engine production subsidiary to develop preventative measures and submit a report by the end of May. The engine maker previously admitted to misconduct in the manufacturing process of its aircraft engine parts back in 2019.