In 2009, tougher vehicle emissions regulations were instituted to protect the environment from the vast amounts of nitrogen oxide that cars were emitting all over the globe. These regulations came at the detriment of automobile manufacturers that produced diesel vehicles, which emit higher rates of nitrogen oxide due to the diesel fuel burned. Volkswagen was one of the first automobile manufactures to release a diesel vehicle that met the new, strict regulations.
Unlike most diesel vehicles that input an additional tank of urea-based solution used to decrease nitrogen oxide emissions, Volkswagen insisted the 2.0 liter four-cylinder engine on its smaller models did not require a rea injection system. They offered little explanation to this; however the vehicles were emitting satisfactory emission levels.
On September 18, it was discovered that Volkswagen has installed a software algorithm in its smaller diesel vehicles that could recognize when a car was being tested for emission levels. When the software suspected the test was occurring, the car would reduce emissions for the purpose of passing the test.
Volkswagen released almost 11 million TDI diesel cars that contained the “defeat device.” The device would deceptively show emission levels that met EPA’s legal limits instead of the true emissions that, in reality, exceeded regulations 10 to 40 times over. The car company has not released an official recall of its products to repair the software.
The cars affected include 2009 to 2015 TDI Volkswagen Golf, Jetta, Beetle, and Audi A3s as well as the 2014 to 2015 Passat. These vehicles are powered by 2.0-liter turbodiesel four-cylinder engines which were theorized to be small enough to not require the AdBlue solution other diesel engines utilized to meet more stringent emissions regulations. The EPA is investigating the case further to establish the scope of consequences from this event.