All about the 2015 Volkswagen TDI emissions problem

What it all means and what to do if your car is affected

2015 Volkswagen Golf front view
2015 Volkswagen Golf. Photo © Aaron Gold

On Friday, September 18th, 2015, the Environmental Protection Agency sent a notice of violation to Volkswagen (which also owns Audi) saying that some of their diesel-powered (TDI) models have a "defeat device" that reduces engine pollution during emissions testing. Volkswagen has admitted to the fault and plans to recall nearly half a million vehicles once a fix has been devised. Additionally, Volkswagen dealers stopped selling new and used TDI models.

(While much of the press is referring to this as a recall, technically, a recall has not been issued, but one is definitely on the way.)

Which Volkswagen and Audi cars are affected?

The violation affects several VW and Audi models that use the 2.0 liter four-cylinder TDI diesel engine:

In total, approximately 480,000 vehicles sold in the US are affected. (UPDATE: According to an article in Automotive News, on the world-wide market, as many as 11 million cars may be affected!)

Note that this recall only affects four-cylinder diesel models. Gasoline and hybrid models are not affected.

UPDATE: On November 2, 2015, the EPA issued a new notice of violation covering VW/Audi's 3.0 liter V6 engine. Models affected:

Unlike the four-cylinder cars, Volkswagen denies that the V6 TDI engines are non-compliant.

What's wrong with the cars?

A third-party group reported to the EPA that the cars were producing higher emissions (specifically nitrogen oxide, or NOx) in real-world driving than in emissions testing.

Investigation revealed that Volkswagen had programmed the car's engine control computer to detect when the car was being tested and reduce fuel flow so as to reduce NOx emissions. In actual driving, the cars produce significantly higher emissions. Volkswagen has acknowledged the "cheat" and issued an apology from its CEO.

Are the recalled Volkswagens and Audis safe to drive?

Yes, the cars are safe to drive. Though the pollution levels of the affected vehicles will be higher, there is nothing that poses an immediate safety threat to the driver or occupants.

What should I do if I own one of the affected cars?

For now, TDI owners can do nothing but wait as Volkswagen works out a solution to the problem. Once the solution is found, Volkswagen will issue a recall notice to owners. Owners will need to bring the cars to a dealership to have the modifications made. As this is an emissions recall, the work will be performed at no cost to the owner.

What are the long-term effects of the VW/Audi emissions recall?

This recall is unusual because it may have long-term repercussions for owners. Depending on how Volkswagen implements its fix, the cars could require extensive reworking, or they could face reduced power and fuel economy as a result.

Because the cars are technically not compliant with emissions standards, and therefore not suitable for sale, registering (or renewing registration) could be a problem in some states, specifically California and other states that comply with California emissions (AZ, CT, DC, ME, MD, MA, NJ, NM, NY, OR, PA, RI, VT, and WA). I contacted the California Air Resources Board (CARB), which sets emissions policy for California, and they said they plan to take no action because the investigation is pending. However, once a fix is agreed upon between VW, the EPA and CARB, owners may have issues with registering or transferring their cars until the fixes have been applied.

What exactly is the problem?

The issue centers around nitrogen oxide (NOx) emissions, which diesel engines produce in higher amounts than gasoline engines.

Most diesels need a system called selective catalyst reduction (SCR) to reduce NOx. SCR uses a special type of fluid (often called AdBlue or Diesel Exhaust Fluid) that reduces emissions. None of the affected cars use an SCR system except for the Passat. (Read about our adventures with SCR and AdBlue in our long-term 2012 Volkswagen Passat TDI, which, incidentally, is not subject to the Notice of Violation.)

Volkswagen claimed they could meet emissions standards without SCR. Apparently, they were wrong.

Why would Volkswagen cheat on emissions tests?

The United States has some of the strictest vehicular emissions standards in the world; engines must be specially tuned to meet American standards. (Same goes for our crash standards, by the way.) Generally, Americans buy enough cars that it's worth investing the time and money to make cars compliant and legal for sale in our market.

Diesel is a bit of a different story. While diesel engines are popular in Europe, here in America, they are much less common, and it is harder to justify the costs of "Federalizing" a diesel car. So why sell them here at all? Because they get fantastic fuel economy, and can help an automaker meet Federally-mandated fuel economy standards. Why spend the money to develop a new hybrid when you have perfectly good diesels being sold in other markets?

However, these diesels must be updated to meet American standards, and that can be tricky. (Mazda's SkyActiv-D diesel, which was supposed to appear in the Mazda6, has been indefinitely delayed for this very reason.) If Volkswagen could not find a way to produce a compliant diesel with adequate power and fuel economy… well, you can see the temptation to cheat, can't you?

Read more: My car has been recalled. Now what?