韩国现代汽车使用的一款四缸发动机有设计和制造问题，给众多消费者造成重大危险和损失。一个吹哨人获两千四百万美元奖励。

https://www.jalopnik.com/1895746/biggest-problem-with-kia-hyundai-theta-2-engines/

The fallout was explosive. Class action lawsuits against Hyundai and Kia started popping up. In September 2015, Hyundai issued a recall for 470,000 Sonatas manufactured from 2010 to 2011 and running 2.0-liter and 2.4-liter Theta II engines. This was followed by a recall in March 2017 that involved 572,000 Sonatas and Santa Fe Sports made from 2013 to 2014,. At the same time, Kia issued a recall for its Optima (2011-2014), Sorento (2012-2014), and Sportage (2011-2013), a total of 618,160 vehicles. 

The tinder in the powder keg came in the form of a whistleblower, a Hyundai safety engineer. He filed a report with the National Highway Transportation Safety Administration citing the delay from Hyundai and Kia in issuing a timely recall. An unlikely hero, like the Tesla whistleblower. 

In the end, the Theta II engine cost Hyundai and Kia over $2 billion in the form of fines, lawsuit settlements, recalls, engine replacements, and offering increased warranty on engines. It's a gift that keeps on giving. The only winner in this entire debacle was the whistleblower, who received a cool $24 million from the NHTSA.