From 2014 onwards, software which manipulated air pollution tests was discovered in vehicles from some car makers; the software recognized when the standardized emissions test was being done, and adjusted the engine to emit less pollutants during the test in order to pass regulatory benchmarks. The cars emitted much higher levels of pollution under real-world driving conditions. Some cars' emissions were higher even though there was no manipulated software.
Scandals relating to higher-than-reported emissions from diesel engines began in 2014 when the International Council on Clean Transportation (ICCT) reported discrepancies between European and US models of vehicles. This began with the Volkswagen emissions scandal. Independent tests carried out by the German car club ADAC proved that, under normal driving conditions, diesel vehicles including the Volvo S60, Renault's Espace Energy and the Jeep Renegade, exceeded legal European emission limits for nitrogen oxide () by more than 10 times. ICCT and ADAC showed the biggest deviations from Volvo, Renault, Jeep, Hyundai, Citroën, and Fiat.NOX control technologies for Euro 6 Diesel passenger cars, Market penetration and experimental performance assessment, Liuhanzi Yang, Vicente Franco, Alex Campestrini, John German, and Peter Mock. ICCT in collaboration with ADAC, 3 September 2015.
Researchers have criticized the inadequacy of current regulations and called for the use of a UN-sanctioned test called Worldwide harmonized Light vehicles Test Procedures that better reflects real-life driving conditions. The test only came into force in 2017, with critics saying that car firms lobbied fiercely to delay its implementation due to the high cost of meeting stricter environmental controls.
Conservative Internal Market spokesman Daniel Dalton, who led the legislation through the European Parliament, described the previous regulations as "at best patchy and at worst ineffective". He further said that his latest 2018 report introduced a strong and transparent system to ensure cars are safe and meet emissions standards. Since 2016, 38 out of 40 diesel cars tested by ADAC failed a -test.
Background Early in the 1950s, scientists discovered that vehicle emissions were a significant factor that had been causing the air quality to deteriorate. This led to the introduction of vehicle emissions standards in California in 1966, furthermore due to the seriousness of the problem, in 1970 the Clean Air Act was introduced in order to regulate these standards all over the United States. Eventually, other countries including European Nations, Australia, Japan and India followed suit. The United States as well as the other countries who followed were quick to act since vehicle emissions became a public health risk. The introduction of these emission standards produced satisfying results, from 1975 to 1996 carbon emissions dropped 76.3% of the initial levels in 1975. Correspondingly, studies estimate that the introduction of these policies averted 19,008 deaths from 1975 to 1996.
Manufacturers Volkswagen
The Volkswagen emissions scandal started on 18 September 2015, when the United States Environmental Protection Agency (EPA) issued a notice of violation of the Clean Air Act to German automaker Volkswagen Group. Volkswagen had intentionally programmed turbocharged direct injection (TDI) diesel engines to activate emissions controls only during emissions testing. In January 2017, VW pleaded guilty to the emissions scandal and agreed to pay US$4.3 billion in penalties. As of January 2019, 13 VW employees have been indicted, including former CEO Martin Winterkorn. In addition, two former executives (Oliver Schmidt and James Robert Liang) have pleaded guilty in US court and sentenced to prison terms.
The 2015 scandal was likely caused by the increasingly strict standards set, paired with the lack of technology to meet these requirements. Moreover, another possible reason for this scandal outbreak is cost. In order for automakers to comply with these standards, they must spend from $800 up to $3,000 more per vehicle. Volkswagen confessed that they could not comply with the policies in the amount of time they had when the standards became more strict in 2005. After much analysis of the Volkswagen company, the rigging was allowed for so long due to failing internal policies.
Audi and Porsche In July 2019, Deutsche Umwelthilfe (DUH) (German Environmental Aid) published a press release in which it states that Porsche-vehicles equipped with Audi-diesel-engines of the Euro 5 and Euro 6 emission standards exceed the limit values for nitrogen oxides () many times over.
The statutory limit for diesel passenger cars Euro 5 is 180 mg /km. The Porsche Panamera equipped with the VW-EA897 engine, made by Audi, exhibited an 8.3-fold limit violation with an average emissions of 1,498 mg/km, according to DUH. According to DUH data, the measurements were made at outside temperatures between +10 and +14 °C. Two Porsche Cayenne with the EA897evo engine (Euro 6) are said to have exceeded the applicable limit of 80 mg/km in normal mode by 3.6 or 4.2 times. Limits exceeding by the Cayenne in normal mode increases according to DUH in sport mode with the same driving style by two times. Also the arranged software update by the Federal Motor Transport Authority (Kraftfahrt-Bundesamt) does not prevent exceeding the limit. A tested Porsche Cayenne, emission standard Euro 6, exceeds the limit by 2.4 times at +10 to +16 °C with an average of 191 mg /km after the software update. In addition, the vehicle with a carbon dioxide emissions of 179 g CO2/km is permitted, but in real operation on the road, according to DUH, the emissions are on average 241 g CO2/km. In addition to the diesel passenger car Audi A8 4.2 TDI with emission standard Euro 6, which according to own data was measured on average 1,422 mg /km, also showed further new measurements on Audi Models High Limit Exceedances. An examined Audi SQ5 plus 3.0 TDI with emission standard Euro 6, with the same engine generation (EA897evo) as the Porsche Cayenne, emits an average of 441 mg / km at outside temperatures between +4 and +11 °C. The measurements were carried out by the DUH according to the press release on the road using PEMS.
Initiated by the measurements, the DUH called on the manufacturers to publish a complete overview of all installed defeat devices for every diesel vehicle and to commit themselves to repair the diesel exhaust gas cleaning for all affected diesel buyers to help a legally compliant vehicle – or to reimburse them the full purchase price. It also announced that it will make the measurements results available to law enforcement agencies, the European Antitrust Authority and all concerned stakeholders and their lawyers. At the same time the DUH renewed their criticism of the Federal Motor Transport Authority and of Andreas Scheuer (Head of Federal Ministry of Transport and Digital Infrastructure), who according to the DUH-President on the one hand restraint documents about the detected defeat devices in the vehicles, despite final convictions for disclosure, and secondly prevent officially ordered hardware retrofits.
IAV IAV GmbH paid a $35 million fine in the US.
Daimler Mercedes-Benz Even though up to 2018 there were increasingly specific allegations of defeat devices in the control software for Mercedes-Benz U.S. cars, Mercedes-Benz denies the charges. As of June 24, 2019 Daimler insisted its diesels didn't break the law. European vehicle emissions rules were loosely written. Turning down or switching off emission controls to protect the engine in certain circumstances – such as lower temperatures – was allowed. Earlier, Feb 2018, German newspaper Bild am Sonntag reported that US authorities investigating Mercedes have discovered that its vehicles are equipped with illegal software to help them pass United States' stringent emission tests. The claimed defeat devices include a mode to switch off emissions control after 16 miles of driving (the length of an official U.S. emissions test), and which tries to directly determine if the car is being tested based on speed and acceleration profiles.
In June 2019, Daimler recalled 60,000 Mercedes diesel powered cars in Germany, the model affected is the Mercedes-Benz GLK 220 SUV produced between 2012 and 2015, car is fitted with software aimed at distorting emissions tests. Germany's vehicle authority, the Federal Motor Transport Authority is looking to extend investigations of cheating devices reportedly used in Daimler's C-Class and E-Class OM642 and OM651 engines. The number could be as high as 700,000 vehicles.Daimler to recall 60,000 Mercedes diesels in Germany over emissions: Daimler to recall 60,000 Mercedes diesels in Germany over emissions, access-date: 25. June 2019 In September 2019, Daimler was fined 870 million euros in Germany for "negligent violation of supervisory duties" in relation to not fully complying with emissions regulations. In 2022, Mercedes settled for $5.5 million in Arizona.
BMW BMW was implicated in an "emissions cartel" which sought to restrict design standards for AdBlue. They were fined €875m along with VW in July 2021. In 2018 BMW recalled 11,700 cars which had incorrect emissions software installed to some diesel cars. The company denied using defeat devices, as suggested by the KBA. BMW was sued in 2018 when certain models were named as producing several times more nitrogen oxide emissions than laboratory tests indicated. They were accused of colluding with Robert Bosch GmbH and LLC to produce defeat software to hide the cars' true emissions.
Opel/Vauxhall (General Motors) Opel, a German brand then owned by General Motors, was caught using a defeat device in Europe in 2015. The engine software changed the engine behavior based on whether two or four wheels were rotating. In an Opel Zafira front-wheel-drive vehicle, the emissions were within the 80 mg/km legal limit – but only when the vehicle was on a test stand, with the front wheels rotating and the rear wheels being stationary. When the rear unpowered wheels were made to rotate too (which is how a front-wheel-drive vehicle behaves on the road), the emission were twice the limit (cold engine) or three to four times the limit (warmed-up engine). In January 2016, the Economic Inspectorate opened an investigation into the suspicious reductions in emissions levels of the Opel Zafira models. Ten Opel dealerships were raided by the authorities.
Opel Zafira emissions, mg/km(all tests performed on the same car)