The Volkswagen Emissions Scandal: What Volkswagen Did

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-pollution mode only during those tests. In normal driving, the same vehicles emitted nitrogen oxides at levels up to 40 times higher than the legal limit set by the U.S. Environmental Protection Agency (EPA). When the company admitted this in September 2015, it became one of the largest environmental frauds in corporate history.

Volkswagen sold approximately 11 million vehicles worldwide with this software, including roughly 500,000 in the United States. The company had marketed these cars as "clean diesel" and environmentally friendly, which was the opposite of what the vehicles actually did on the road. The deception affected models including the Jetta, Beetle, Golf, and Passat, primarily from model years 2009 through 2015.

The scandal emerged when researchers at West Virginia University tested Volkswagen diesels on the road and found their emissions far exceeded lab results. The EPA then investigated and discovered the deliberate software. Volkswagen initially claimed a "technical problem," then admitted the truth after internal investigations revealed the deception went back years and involved multiple levels of the company.

Key Takeaways

  • Volkswagen programmed diesel engines to pass emissions tests while polluting heavily during normal driving, affecting 11 million vehicles worldwide and roughly 500,000 in the United States.
  • The scandal exposed how nitrogen oxide pollution from diesel vehicles harms air quality and human health, particularly in cities and near highways.
  • Volkswagen paid over $15 billion in fines, settlements, and buyback programs in the United States alone, and faced criminal charges against executives.
  • The scandal led to stricter emissions testing procedures, including real-world driving tests that cannot be defeated by software tricks.
  • Owners of affected vehicles had options to sell the car back to Volkswagen, have it repaired, or receive compensation, depending on their location and vehicle model.

Why Nitrogen Oxides Matter for Air Quality and Health

Nitrogen oxides (NOx) are pollutants that form when fuel burns at high temperatures. They contribute to smog, acid rain, and ground-level ozone, all of which damage air quality. When people breathe air with high NOx levels, it can trigger asthma attacks, reduce lung function, and increase the risk of respiratory infections. Children, older adults, and people with existing lung disease face the greatest risk.

Diesel engines produce more nitrogen oxides than gasoline engines because of how they operate. The EPA sets legal limits on how much NOx a vehicle can emit to protect public health. Volkswagen's vehicles were emitting far above those limits during real driving, which meant they were contributing significantly more pollution than the law allows. In cities and areas with heavy traffic, this kind of excess pollution can measurably worsen air quality for everyone living nearby.

The scandal highlighted a gap in how emissions were tested: the EPA tested vehicles in controlled lab conditions, not in real-world driving. Volkswagen exploited this gap by programming engines to behave differently during tests. This discovery led regulators worldwide to change how they test emissions, moving toward real-world driving tests that are harder to manipulate.

The Financial and Legal Consequences for Volkswagen

Volkswagen faced penalties totaling more than $15 billion in the United States, making it one of the costliest environmental settlements ever. The company paid $10 billion to settle with the EPA and the National Highway Traffic Safety Administration (NHTSA), $4.3 billion to settle with the Department of Justice, and additional amounts to individual states and owners. Globally, the costs exceeded $30 billion.

Beyond fines, Volkswagen was required to buy back or repair affected vehicles. The company spent billions on a buyback program that allowed owners to sell their cars back to Volkswagen at fair market value. For vehicles that were repaired instead, Volkswagen had to install equipment to reduce emissions, though some owners questioned whether repairs could fully solve the problem.

Criminal charges were filed against Volkswagen executives, including the company's former CEO. Several executives were convicted and served prison time. The scandal damaged Volkswagen's reputation and led to leadership changes, a shift in company strategy toward electric vehicles, and ongoing scrutiny from regulators.

How the Scandal Changed Emissions Testing Worldwide

Before the scandal, the EPA tested vehicle emissions in a lab using a standardized driving cycle that did not reflect real-world conditions. Volkswagen's engineers knew this and programmed the software to recognize the test pattern. After the scandal broke, the EPA and regulators in Europe, Japan, and other countries overhauled their testing procedures.

The new standard in the United States is called the Worldwide Harmonized Light Vehicle Test Procedure (WLTP). It includes real-world driving emissions (RDE) testing, where vehicles are driven on actual roads with portable emissions measurement equipment. This type of test is much harder to cheat because the driving patterns are varied and unpredictable. Regulators also increased the frequency of inspections and added penalties for software that detects testing conditions.

The scandal also prompted stricter oversight of vehicle software. Regulators now require manufacturers to disclose software that affects emissions and to justify why it is necessary. This transparency makes it harder for companies to hide pollution-control tricks in their code.

What Happened to Owners of Affected Vehicles

Volkswagen owners in the United States had three main options: sell the car back to Volkswagen through the buyback program, have the vehicle repaired, or receive a cash settlement. The buyback program offered owners the vehicle's pre-scandal market value, which was often higher than what they could sell it for privately once the scandal became public. Owners who chose repair received their vehicle back with emissions equipment installed, plus compensation.

The process varied by state and vehicle model. Some owners received larger settlements than others based on the specific vehicle and when they purchased it. Owners had to provide proof of ownership and a clear title. The buyback and repair programs ran for several years after the scandal, though some ended before all owners could participate.

Owners who kept their vehicles after repair faced uncertainty about resale value and long-term reliability. Some reported that repaired vehicles had reduced fuel economy or performance. Others found that the stigma of owning a "cheater car" made it harder to sell, even after repairs were completed.

The Broader Impact on the Auto Industry and Consumer Trust

The Volkswagen scandal shook consumer confidence in diesel vehicles and raised questions about whether other manufacturers had similar problems. Regulators launched investigations into other companies, and some found violations, though none as widespread as Volkswagen's. The scandal made consumers more skeptical of environmental claims made by car companies and more aware that real-world performance can differ from lab results.

The scandal also accelerated the auto industry's shift toward electric vehicles. Volkswagen, in particular, committed billions of dollars to developing and manufacturing electric cars as part of its recovery strategy. Other manufacturers increased their electric vehicle investments partly in response to the scandal and the stricter emissions standards that followed.

For regulators, the scandal demonstrated the importance of real-world testing and oversight. It led to more resources for emissions testing, more frequent inspections, and stronger penalties for violations. The lesson was clear: companies will exploit loopholes if the incentive is strong enough, so regulations must be designed to prevent cheating, not just to catch it after the fact.

Frequently Asked Questions

Did other car manufacturers cheat on emissions tests?

Some other manufacturers were found to have used software that reduced emissions during testing, but not to the extent Volkswagen did. Investigations found violations at Fiat Chrysler, BMW, and others, but these were generally smaller in scale. Volkswagen's scandal was unique in its deliberate, systematic nature across millions of vehicles.

Can a repaired Volkswagen diesel still pollute more than it should?

Repaired vehicles have equipment installed to reduce emissions, but some owners and researchers have questioned whether repairs bring emissions fully into compliance under all driving conditions. The repairs were designed to meet the new testing standards, but real-world performance can vary based on driving style, maintenance, and other factors.

Why did Volkswagen choose to cheat instead of just making cleaner engines?

Volkswagen wanted to sell diesel vehicles that were both powerful and fuel-efficient while meeting emissions limits. The company believed it could not achieve all three goals with the technology available at the time, so it chose to cheat rather than compromise on performance or fuel economy. The decision was driven by profit and market competition, not technical necessity.

Are diesel vehicles still sold in the United States?

Yes, diesel vehicles are still sold, but in much smaller numbers than before the scandal. Manufacturers have invested in cleaner diesel technology, and some consumers remain interested in diesel for its fuel economy. However, many buyers shifted to gasoline or electric vehicles after the scandal reduced confidence in diesel.

What does the scandal tell us about environmental regulations?

The scandal showed that regulations are only as strong as the testing that enforces them. When testing is predictable and controlled, companies can design software to pass tests without actually reducing pollution in real driving. The shift to real-world testing and increased oversight reflects the lesson that regulators must stay ahead of companies' ability to exploit loopholes.