The Volkswagen Emissions Scandal: What Happened

Between 2009 and 2015, Volkswagen installed software in millions of diesel vehicles that detected when the car was being tested for emissions and switched the engine to a low-emissions mode only during those tests. In real-world driving, the vehicles emitted nitrogen oxides at levels up to 40 times higher than the legal limit. The company knowingly sold these vehicles as "clean diesel" and concealed the software from regulators in the United States, Europe, and other countries.

The scandal came to light in September 2015 when researchers at West Virginia University discovered the discrepancy between test results and actual emissions. Volkswagen initially claimed a "technical problem," then admitted the deliberate deception. The company eventually recalled roughly 11 million vehicles worldwide, including about 500,000 in the United States.

Volkswagen paid over $15 billion in fines, settlements, and buyback costs in the U.S. alone. Criminal charges were filed against company executives, and the scandal damaged the reputation of diesel engines in the American market for years afterward.

Key Takeaways

  • Volkswagen used defeat devices—software that reduced emissions only during official tests—in diesel vehicles sold between 2009 and 2015.
  • If you own a affected VW, Audi, or Porsche diesel vehicle, you were may have access to to a recall repair, buyback, or cash settlement depending on the model year and your location.
  • The scandal led to stricter emissions testing procedures in the U.S. and Europe, including real-world driving emissions tests that are harder to cheat.
  • Owners of recalled vehicles should verify their vehicle's repair status through Volkswagen's official recall database or their dealer.

Which Vehicles Were Affected

The scandal involved diesel vehicles from Volkswagen, Audi, and Porsche brands. In the United States, the primary affected models were the 2009–2015 Volkswagen Jetta, Golf, Beetle, and Passat with 2.0-liter diesel engines, and the 2014–2015 Volkswagen Touareg with a 3.0-liter diesel engine. Audi A3 models from 2009–2015 and certain Porsche Cayenne models were also included.

Later investigations revealed that some gasoline-engine vehicles and vehicles sold in other markets were also affected by similar software. The scope expanded beyond the initial 2009–2015 window for some model lines and regions.

To find out whether your specific vehicle was part of a recall, you can check the National Highway Traffic Safety Administration (NHTSA) website using your vehicle identification number (VIN), or contact a Volkswagen dealer directly with your VIN.

Recall Remedies: Repair, Buyback, or Settlement

Volkswagen offered three main remedies to U.S. owners of affected vehicles. The first was a recall repair—a software update and hardware modifications designed to bring emissions into compliance. The second was a buyback program, in which Volkswagen repurchased the vehicle at a price based on its pre-scandal market value, regardless of current mileage or condition. The third was a cash settlement for owners who chose to keep their vehicles after the repair was completed.

The buyback option was available to most owners, though some 2015 model year vehicles were excluded. Settlement amounts varied by model year and engine size. Owners who chose the buyback could keep their vehicle and receive additional compensation if they agreed to return it, or they could return it and receive the full buyback amount.

The important date to file a claim under the original settlement was in 2018, but some claims continued to be processed afterward. If you own an affected vehicle and did not participate in the recall or settlement, contact a Volkswagen dealer to understand your current options.

How the Scandal Changed Emissions Testing

Before the scandal, the U.S. Environmental Protection Agency (EPA) relied primarily on standardized laboratory tests to measure vehicle emissions. These tests were conducted on a dynamometer—a machine that simulates driving—under controlled conditions. The Volkswagen scandal exposed how straightforward it was for manufacturers to optimize their vehicles to pass these tests while performing poorly in real-world driving.

In response, the EPA and the California Air Resources Board (CARB) introduced real-world driving emissions (RDE) testing for new vehicles. RDE testing involves driving vehicles on actual roads with portable emissions measurement systems (PEMS) to measure what comes out of the tailpipe in normal conditions. This approach is much harder to circumvent with software tricks because the test conditions are unpredictable and varied.

The scandal also led to increased scrutiny of manufacturer testing data and more frequent audits by regulators. Some countries, including Germany, launched investigations into other manufacturers and found similar defeat devices in vehicles from other brands.

What Owners Should Know About Their Recalled Vehicle

If you own a Volkswagen, Audi, or Porsche diesel vehicle from the affected years, the first step is to confirm whether your specific vehicle was recalled. Use the NHTSA website (safercar.gov) or contact your local Volkswagen dealer with your VIN. The dealer can tell you whether a recall repair has already been completed on your vehicle or whether it is still pending.

If a repair has not been completed, you can schedule one at any Volkswagen dealer at no cost to you. The repair typically takes a few hours and involves a software update plus hardware changes such as a new catalytic converter or diesel particulate filter, depending on the model. After the repair, your vehicle should pass standard emissions inspections.

If you are considering buying a used Volkswagen diesel from the affected years, ask the seller or dealer whether the recall repair has been completed. A vehicle with an uncompleted recall may fail an emissions inspection in some states, and you could be responsible for completing the repair yourself.

Emissions Inspection and Your Recalled Vehicle

After a recall repair is completed, your vehicle should pass a standard emissions inspection in any state that requires one. The repair brings the vehicle into compliance with EPA standards for the model year it was sold.

However, if you are in a state with stricter emissions standards—such as California, New York, or Massachusetts—your vehicle must also meet those state standards. In most cases, a vehicle that passes the federal EPA test will also pass state tests, but you should verify this with your state's emissions testing program before purchasing or keeping a recalled vehicle.

If you have questions about whether your specific vehicle will pass inspection in your state after the recall repair, contact your state's environmental agency or the Volkswagen dealer handling the repair.

The Broader Impact on Diesel and Vehicle Emissions

The Volkswagen scandal significantly damaged consumer confidence in diesel vehicles in the United States. Sales of new diesel cars dropped sharply after 2015, and many manufacturers reduced or eliminated their diesel passenger car offerings in the American market. Diesel remains common in trucks and commercial vehicles, but the scandal made consumers skeptical of diesel's environmental claims.

The scandal also raised awareness of the gap between laboratory test results and real-world emissions across all vehicle types and manufacturers. This has led to greater consumer interest in electric vehicles and hybrid technology as alternatives to traditional gasoline and diesel engines.

For regulators, the scandal demonstrated the need for stronger oversight of manufacturer testing and more transparent reporting of emissions data. The shift toward real-world driving emissions testing is expected to continue as a standard practice globally.

Frequently Asked Questions

Can I still drive my Volkswagen diesel vehicle if the recall has not been completed?

Yes, you can drive it legally. However, if your state requires emissions inspections, an unrepaired vehicle may fail that test. Additionally, if you plan to sell the vehicle, a potential buyer may discover the uncompleted recall and negotiate a lower price or decline the purchase.

Will the recall repair affect my vehicle's performance or fuel economy?

The repair may slightly reduce fuel economy and engine performance compared to the unrepaired state, because the vehicle will no longer be running in the cheating mode. However, the repair brings the vehicle into compliance with the emissions standards it was supposed to meet when sold.

What if I already completed the buyback and returned my vehicle to Volkswagen?

If you participated in the buyback program, your claim was settled. You cannot reopen a completed buyback claim. If you believe you were treated unfairly or missed a important date, you can contact the settlement administrator or a lawyer who specializes in consumer claims, though most important date have passed.

Do other car manufacturers have similar defeat devices?

Investigations after the Volkswagen scandal found similar software in vehicles from other manufacturers, including some Audi, Porsche, and Mercedes-Benz models. However, the Volkswagen scandal was the largest and most systematic. If you own a vehicle from another manufacturer and are concerned, check the NHTSA website for any recalls related to your specific model.

How do I know if my vehicle passed the recall repair inspection?

After the repair is completed, the dealer will provide you with documentation. You can also contact your local Volkswagen dealer with your VIN to confirm the repair status. Some states' emissions testing programs can also verify whether a vehicle has passed inspection after a recall repair.