Audi was caught cheating on its diesel emissions with defeat devices. Twice. It started with the widespread dieselgate story for 2.0L 4-cylinder engines and was followed with a lesser known cheat for vehicles with the ZF 8-speed transmission.
Back in 2008, the Environmental Protection Agency (EPA) implemented tougher emissions standards for cars. That forced automakers to come up with creative solutions to balance their emissions output with consumer demand for fuel economy and performance.
Diesel engines have great fuel efficiency and power, but they also run dirty. So to meet regulations most companies started adding a urea-based solution, known as AdBlue, to their vehicles. There's a bit science involved here but basically it helps the catalytic converter convert bad things (nitrous oxide) into good things (nitrogen and water).
In both Audi and VW 2.0L 4-cylinder diesel engines, they skipped the AdBlue and used an NOx trap instead. Those traps typically require the engine to use more fuel, but "clean diesels" didn't take an MPG hit.
2016 was the year of emissions cheating. VW's diesel emissions scandal resulted in so many headlines. So. Many. Headlines. It sure would have been nice to finish the year without having to mutter the words "defeat" or "device" between sips of eggnog.
But then a report by the German paper Bild am Sonntag scrooged up my holiday plans when they announced that CARB had discovered another defeat device on potentially hundreds of thousands of Audi vehicles. Swell.
The device used on these Audis is completely different than the one VW was caught using on its diesel engines. For starters, this one is part of the transmission – the ZF8 8-speed, automatic AL 551 transmission, to be exact. The device is also meant to skirt carbon dioxide emissions on both diesel and gas engines.
The device is simple. Painfully simple. When the Audi is started up the transmission engages a "low C02" program and then starts monitoring the steering wheel. If the steering wheel is never turned more than 15 degrees – like say in a testing lab – the program keeps humming along all clean and green. When the steering wheel is turned, however, the program shuts off and the car starts spewin' out carbon dioxide above the legal limit.
It's estimated the devices were installed in Audi cars until May 2016. For those keeping score at home, that's waaaaay after the other VW emissions scandal hit the news. What's German for cojones?