How Volkswagen Cheated On The Diesel EPA Test And Got Caught
By Paulo Acoba
Volkswagen was ordered to recall close to 500,000 of their cars after being caught cheating on the EPA diesel test six years later.
If there’s one group you never want to catch you “slipping up” it’s the California Environmental Protection Agency. Earlier today (Sept. 18, 2015) the California Air Resource Board issued a statement saying that Volkswagen “allegedly used software that circumvents emissions testing for certain air pollutants.” In short, during the EPA’s test for diesel emissions a piece of software would recognize that they were going through government mandated testing and would turn on the whole suite of emissions controls. But in normal everyday driving, a large chunk of those emissions controls would be turned off thus allowing for more power and subsequently higher emissions of Nitrogen Oxide out of the tailpipe. The EPA reported that with emission controls off in these certain VW’s, emissions were over 40 times the legal limit in some cases. Here are the list of vehicles affected,
- Jetta (Model Years 2009 – 2015)
- Beetle (Model Years 2009 – 2015)
- Audi A3 (Model Years 2009 – 2015)
- Golf (Model Years 2009 – 2015)
- Passat (Model Years 2014 – 2015)
California’s Diesel regulations are some of the strictest in the nation and if you’re going to be selling vehicles with diesels in California, you’d better have your emissions up to snuff. Mazda tried to introduce a diesel version of their Mazda 6 sedan earlier this year but found that although they passed the EPA diesel test with flying colors, their 2.2 SkyACTIV diesels were just too slow for their liking. Diesels like trucks that DO sell in California use a urea injection system called SCR which introduces a urea mixture into the exhaust stream after combustion (You can read up on how this affects diesels thanks to Cummins here.) Decomposition of urea in the hot exhaust gas stream makes ammonia which combines with the nitrogen oxide to produce water and nitrogen, both harmless to the environment. SCR systems are very expensive and when added to a vehicle, inflate the price for the customer as well as add extra cost for engineering and implementation. In addition, Diesel Exhaust Fluid (or DEF) must be replenished by the user every couple of thousand of miles, another added cost and inconvenience that VW didn’t want to pass on to their consumer.
Thanks to our motoring friends over at Jalopnik, NGN_DZNR gave us some insight of what VW might have done…
"If its NOx, it’s most likely EGR they were playing with. The calibration to pass emissions had high EGR (low NOx) while the cheater version had low EGR (high NOx). Downside of high EGR is less power due to recirculated exhaust gas displacing the air (and oxygen) that would normally be ingested. Because less oxygen is going in, less fuel is being injected to maintain same air-fuel ratio yielding less power. VW probably felt that the consumer would complain the car wasn’t peppy enough if they had their “passing” calibration on all the time. As long as the “passing” calibration was on during the driving of the “simulated” testing criteria, I don’t see how this is illegal unless the ECU could detect when it was actually being tested vs not tested while driving the simulated testing course and change accordingly."
This infographic posted below should help as well. (Photo Credit: Reuters)
And it looks like the EPA and the California Resource Board were aware of these devices all along as they had already initiated an investigation whose intent was to find these devices. According to the NY Times, ” Officials from E.P.A. and the California Air Resources Board said they discovered the software in the course of an investigation aimed at uncovering the use of such defeat devices. They said that researchers at West Virginia University and the International Council on Clean Transportation, a nongovernmental organization, raised questions about emissions levels in the Volkswagen vehicles.“We developed a test routine to demonstrate how they operated one way on a test cycle and another way in the real world.”
These violations carry a maximum fine of more than $35,000 per vehicle. That means in total VW potentially is looking down the barrel of a $18 billion fine. Owners of those cars shouldn’t need to worry. VW, as ordered, will come up with a recall plan that will see these cars come in for free repair to dealerships that will most likely see their software set to run as it’s supposed to. Subsequently we may see the performance of these cars reduced as well as MPG. Don’t be surprised if some customers are refunded a bit for their troubles.