Diesel emissions scandal

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

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 during the test. 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 (NOx) by more than 10 times.[1] ICCT and ADAC showed the biggest deviations from Volvo, Renault, Jeep, Hyundai, Citroën and Fiat.[2][3][1]

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.[3]

Conservative Internal Market spokesman Daniel Dalton[4] – 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, transparent system to ensure cars are safe and meet emissions standards.

Nitrogen oxide (NOx) on-road emissions by manufacturer and capacity[5]
  Average NOx emission (g/km)
  Euro 6 NOx emission limit (g/km)

Since 2016, 38 out of 40 diesel cars tested by ADAC failed a NOx-test.[6]



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.[7]

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.[8][9]

Fiat Chrysler[edit]

On 12 January 2017, the EPA issued a notice of violation to Fiat Chrysler Automobiles (FCA) alleging that over 100,000 model year 2014, 2015, and 2016 diesel SUVs and trucks, including Dodge Ram 1500 and Jeep Grand Cherokee trucks, had software that allowed them to exceed NOx pollution limits, undetected by the usual testing methods. The EPA discovered this during their expanded vehicle tests following the Volkswagen case. FCA was not accused of intentionally cheating on emissions testing, though the EPA did accuse the company of failing to notify the government of the defeat device programming. The US Justice Department was assisting the EPA in their investigation, suggesting the possibility of criminal charges. This is all while FCA executives were hopeful that after the inauguration of President Donald Trump it would be possible to "work with the new administration to try and get this issue behind us", according to FCA CEO Sergio Marchionne.[10][11] Executives denied any wrongdoing but stated to make extensive changes to their vehicle software to address the EPA's concerns.[12]

As part of a January 2019 settlement, Fiat Chrysler recalled and repaired approximately 100,000 automobiles equipped with a 3.0-litre V6 EcoDiesel engine having a prohibited defeat device, pay $311 million in total civil penalties to US regulators and CARB, pay $72.5 million for state civil penalties, implement corporate governance reforms, and pay $33.5 million to mitigate excess pollution. The company will also pay affected consumers up to $280 million and offer extended warranties on such vehicles worth $105 million. The total value of the settlement is worth about $800 million, though FCA did not admit liability, and it did not resolve an ongoing criminal investigation.[13]

In October 2020, Fiat Chrysler faced a £5 billion class-action lawsuit in the UK due to over half a million Fiat, Alfa Romeo, Jeep, Iveco and Suzuki vehicles having these defeat devices.

In connection with the mentioned software, Emanuele Palma, a diesel drivability and emissions senior manager at Fiat Chrysler, was charged with one count of conspiracy to defraud the United States, to violate the Clean Air Act and to commit wire fraud. Palma was also charged with six counts of violating the Clean Air Act, four counts of wire fraud and two counts of making false statements to representatives of the FBI and the EPA's Criminal Investigation Division (EPA-CID).[14] On 3 March 2021, Sergio Pasini and Gianluca Sabbioni, two Italian nationals and alleged co-conspirators of Palma, were indicted.[15]

In 2022 FCA US, formerly Chrysler Group, pleaded guilty to one count of conspiracy to defraud the US, commit wire fraud, and to violate the Clean Air Act.[16]


Jeep, also manufactured by Fiat Chrysler Automobiles, was tested by the consumer group Which? and in March 2017 found to produce 1.74 g/km NOx compared to the 2009 European emission standards Euro 5 legal limit of 0.18 g/km.[17] High level of pollutants were emitted by Jeep Grand Cherokee when its engine was hot.[18]

Opel (General Motors)[edit]

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 NOx 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 NOx emission were twice the limit (cold engine) or three to four times the limit (warmed-up engine).[19][20][21]

Opel Zafira NOx emissions, mg/km[21]
(all tests performed on the same car)

Despite the facts, Opel denied using defeat devices, called the tests "untrustworthy" and "incomprehensible", and one of the scientists involved in testing the car and discovering the discrepancy, Professor Jan Czerwinski from the Bern University of Applied Sciences, was pressured into issuing a statement to a news agency saying that "the facts could be distorted, incomplete or tendentious for various reasons". That was despite those tests being done according to the established (and undemanding) NEDC prodedure.[21][22]

Opel publicly demonstrated (while representatives from the TÜV Hessen were present) a Zafira that met the NOx emission limits.[22] At the same time, Opel started clandestinely pushing an engine software update that limited NOx emissions in Zafiras that were already on the road, and was caught doing so by Belgian journalists from the VRT news station. The software update dramatically lowered NOx emissions in the cars, and was installed in customers' cars during service center visits without their knowing.[23][24][25][26][27]


In September 2015 Renault-Nissan CEO Carlos Ghosn said it would be difficult for an automaker to conceal internally an effort to falsify vehicle emissions data, as happened at Volkswagen AG: "I don't think you can do something like this hiding in the bushes."[28]

In May 2016, South Korean authorities accused Nissan of using a defeat device for manipulating emissions data for the British-built Nissan Qashqai, allegations which the Japanese carmaker denied.[29] In March 2017, Nissan vehicles tested by Which? were found to produce 0.81 g/km NOx compared to the 2009 European emission standards Euro 5 legal limit of 0.18 g/km.[citation needed]


Renault issued press statements reaffirming their vehicles' compliance with all regulations and legislation for the markets in which they operate in 2015.[30]

Headquarters of Renault and Peugeot were raided by fraud investigators in January and April 2016, respectively. Renault subsequently recalled 15,000 cars for emission testing and fixing.[31][32][33]

Since 2015, Renault has been investigated by the French Direction générale de la concurrence, de la consommation et de la répression des fraudes (DGCCRF). Their 2017 report states "the suspicion of the installation of a 'fraudulent device' which specifically modifies the functioning of the engine to reduce emissions of NOx (nitrogen oxides) in conditions specific to the regulatory tests." It affects 900,000 vehicles. Renault Captur and Clio IV exceeded the threshold for carbon dioxide emissions by 377% and 305%.[34]

In 2019, Renault's Clio and Captur diesel models were found to emit more pollutants outside of official test conditions, their exhaust treatment did not work in everyday use when the outside temperature range was below or above those covering official tests.[35][36] Furthermore, their "NOx trap" devices did not run cleaning cycles below 50 kilometres per hour (31 mph), causing those filters to clog and become ineffective.[35]


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.[37] 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 Bit 15 mode to switch off emissions control after 16 miles of driving (the length of an official U.S. emissions test), and Slipguard which tries to directly determine if the car is being tested based on speed and acceleration profiles.[38][39][40]

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.[41][42]

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.[43]

Audi & Porsche[edit]

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 (NOx ) many times over.[44]

The statutory NOx limit for diesel passenger cars Euro 5 is 180 mg NOx/km. The Porsche Panamera equipped with the VW-EA897 engine, made by Audi, exhibited an 8.3-fold limit violation with an average NOx 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 NOx 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 NOx/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 NOx/km, also showed further new measurements on Audi Models High NOx 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 NOx/ 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.


BMW were implicated in an "emissions cartel" which sought to restrict design standards for AdBlue fuel additive. They were fined €875m along with VW in July 2021.[45]

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.[46]

BMW were sued in 2018 as it was suggested that certain models produced several times more nitrogen oxide emissions than laboratory tests suggested. They were accused of colluding with Robert Bosch GmbH and LLC to produce defeat software to hide the cars' true emissions.[47]

Previous defeat device cases[edit]

The Volkswagen TDI diesel emissions case is not the first use of defeat devices by Volkswagen or other automakers nor the first time automakers have taken advantage of their foreknowledge of the specific lab test conditions in order to engage emissions controls only during testing, but not during normal driving.[48]

In 1973 Chrysler, Ford, General Motors, Toyota, and Volkswagen had to remove ambient temperature switches which affected emissions, though the companies denied intentional cheating and said that strategies like enriching fuel mixture during cold engine warm-up periods could reduce overall pollution.[49][50][51] The switches were ordered to be removed from production but cars already on the road did not have to be recalled, and fines were relatively modest.[50][51]

In 1996, GM had to pay a near-record fine of $11 million, and recall 470,000 vehicles, because of ECU software programmed to disengage emissions controls during conditions known to exist when the cars were not being lab tested by the EPA.[52] The model year 1991–1995 Cadillacs were programmed to simply enrich the engine's fuel mixture, increasing carbon monoxide (CO) and unburned hydrocarbon (HC) pollution, any time the car's air conditioning or heater was turned on, since the testing protocol specified they would be off.[52]

In 1996, Fiat of Brazil paid a record fine because of the Fiat Mille Electronic, a very popular version of the Fiat Uno with a 1.0-litre engine. They sold 500,000 vehicles with a combination of carburettor and digital ignition that uses different strategies for laboratory or street driving conditions.[citation needed]

In 1998, Honda Motor Company had to spend $267 million to correct the disabling of the misfire monitoring device on 1.6 million 1996 and 1997 model year vehicles, and Ford Motor Company paid $7.8 million for programming 60,000 1997 Ford Econoline vans to exceed emissions standards during normal highway cruising speeds.[53]

A timer-based strategy was used by seven heavy truck manufacturers, Caterpillar Inc., Cummins Engine Company, Detroit Diesel Corporation, Mack Trucks, Navistar International, Renault Véhicules Industriels, and Volvo Trucks, who in 1998 paid the largest ever fine to date, $83.4 million, for, in the same manner as Volkswagen, programming trucks to keep NOx emissions low during the test cycle, and then disabling the controls and emitting up to three times the maximum during normal highway driving.[54]

The goal of both the Ford and the heavy truck defeat devices was better fuel economy than could be achieved under pollution limits.[54] The major truck manufacturers also had to spend up to $1 billion to correct the problem, which affected 1.3 million heavy duty diesel trucks.[48][54]

While Volkswagen's actions have precedents, the Center for Auto Safety's Clarence Ditlow said that Volkswagen "took it to another level of sophisticated deception we've never seen before."[48]

EU vehicle approval procedures[edit]

In May 2017, the 28 EU member states agreed to begin negotiations with EU institutions to revise the method of testing vehicle emissions towards real circumstances, with random testing of vehicles on the roads and fines for manufacturers who breach the rules.[55]

Eben Moglen has suggested in 2010 to make proprietary software source code in general accessible to the public, to curb cheating.[56][57]

See also[edit]


  1. ^ a b "Wide range of cars emit more pollution in realistic driving tests, data shows", The Guardian, 30 September 2015, retrieved 1 October 2015
  2. ^ 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.
  3. ^ a b "Volkswagen emissions scandal: More carmakers implicated as tests reveal pollution levels of popular diesels", The Independent, retrieved 1 October 2015
  4. ^ "New rules will prevent another Dieselgate scandal - Conservative MEPs". conservativeeurope.com. Retrieved 20 June 2018.
  5. ^ Valentino, Stefano (18 June 2018). "Diesel engines emissions exceed by far European limits". Stefano Valentino/MOBILEREPORTER/VOXEUROP/EDJNet. Retrieved 27 August 2018.
  6. ^ Buric, Christian (20 March 2017). "Verschärfter ADAC EcoTest: auch Benziner mit zu hohen Feinstaubwerten" [Stronger ADAC EcoTest: also petrol with too high fine particle count]. ADAC (in German). Retrieved 25 March 2017.
  7. ^ US EPA, OAR (2015-10-28). "Learn About Volkswagen Violations". www.epa.gov. Retrieved 2022-01-28.
  8. ^ "VW seeks damages from ex-managers for emissions scandal: report". Reuters. 10 January 2019. Retrieved 11 January 2019.
  9. ^ Krisher, Tom (18 January 2019). "Grand jury charges 4 Audi managers in emissions case". AP Nres. Associated Press. Retrieved 18 January 2019.
  10. ^ Snavely, Brent (January 13, 2017), "How Fiat Chrysler's diesel woes differ from VW scandal", Detroit Free Press, USA Today
  11. ^ Valentine, Julia P. (January 12, 2017), EPA Notifies Fiat Chrysler of Clean Air Act Violations; FCA allegedly installed and failed to disclose software that increases air pollution from vehicles, United States Environmental Protection Agency
  12. ^ Overly, Steven; Dennis, Brady (12 January 2017). "EPA: Fiat Chrysler used software to cheat on emissions tests". The Washington Post. Retrieved 12 January 2017.
  13. ^ Shepardson, David (10 January 2019). "Fiat Chrysler agrees to $800 million U.S. diesel-emissions settlement". Reuters. Retrieved 11 January 2019.
  14. ^ Spector, Mike; Shepardson, David (24 September 2019). "Fiat Chrysler manager lied about emissions even after VW scandal broke, indictment charges". Reuters. Retrieved 24 September 2019.
  15. ^ "Two Senior Managers in Italy Charged with Conspiracy to Cheat U.S. Emissions Tests and Defraud U.S. Consumers" (Press release). U.S. Department of Justice – Office of Public Affairs. 20 April 2021. Retrieved 20 April 2021.
  16. ^ "FCA US LLC Sentenced in Connection with Conspiracy to Cheat U.S. Emissions Tests" (Press release). August 1, 2022. Retrieved August 8, 2022.
  17. ^ "Emission Standards: Europe: Cars and Light Trucks". dieselnet.com. Retrieved 2020-11-26.
  18. ^ Sterling, Toby (2017-07-10). "Jeep, Suzuki may have violated emissions rules: Dutch watchdog". Reuters (in German). Retrieved 2020-11-26.[dead link]
  19. ^ "Opel Dealers Accused of Modyfing the Software of Polluting Cars – Slashdot".
  20. ^ http://www.duh.de/uploads/media/PR_High_nitrogen_oxide_emissions_Opel_Zafira_Diesel_231015.pdf[bare URL PDF]
  21. ^ a b c http://www.duh.de/uploads/media/DUH_test_report_nox_231015-unofficial_translation.pdf[bare URL PDF]
  22. ^ a b "Vorwürfe gegen Opel: Berner Abgasprüfstelle rückt von DUH ab".
  23. ^ "Economic Inspectorate to investigate Opel Belgium". 22 January 2016.
  24. ^ "GM's Dieselgate: Mechanics privately admit software update removes crimeware from Opel cars". 19 January 2016.
  25. ^ "VRT NWS: News". Archived from the original on 2016-08-19.
  26. ^ "VRT NWS: News". Archived from the original on 2018-03-07.
  27. ^ VRT, Dutch-language: 1,2,3,4
  28. ^ "Nissan CEO says it would be hard to hide any effort to falsify emissions data". Reuters.
  29. ^ "Nissan to be fined over $380,000 for emissions cheating in South Korea, environment ministry says". Australian Broadcasting Corporation. 16 May 2016. Retrieved 19 May 2016.
  30. ^ VW Emissions Scandal: Motor Industry Reaction, Sky (United Kingdom), retrieved 1 October 2015
  31. ^ Toor, Amar (19 January 2016). "Renault to recall 15,000 vehicles for emissions tests in wake of VW scandal". The Verge. Retrieved 20 January 2016.
  32. ^ "Renault to modify 15,000 new cars in emission scare". UK: BBC News. 19 January 2016. Retrieved 21 January 2016.
  33. ^ "Renault to modify 15,000 new cars in emission scare". UK: BBC. 19 January 2016. Retrieved 22 April 2016.
  34. ^ "Renault in emissions test fix report". The Connexion. 15 March 2017.
  35. ^ a b "Renault diesel allegations upheld by court study: report". Reuters. 13 May 2019. Retrieved 6 November 2019.
  36. ^ Patel, Tara; Nussbaum, Ania (13 May 2019). "Renault Investors Rattled by Report on Faulty Car Emissions". www.bloomberg.com. Retrieved 6 November 2019.
  37. ^ "Mercedes Isn't Looking Too Reliable These Days". Bloomberg. Retrieved 13 Oct 2019.
  38. ^ "Daimler may have used software to cheat on US emissions tests". Engadget. Retrieved 20 June 2018.
  39. ^ Editorial, Reuters (18 February 2018). "Software may have helped Daimler pass U.S. emissions tests: report". Reuters. Retrieved 20 June 2018.
  40. ^ "Abgasskandal: US-Ermittler belasten Daimler schwer". 18 February 2018. Retrieved 20 June 2018 – via Spiegel Online.
  41. ^ Daimler to recall 60,000 Mercedes diesels in Germany over emissions: Daimler to recall 60,000 Mercedes diesels in Germany over emissions, accessdate: 25. June 2019
  42. ^ "Neue Diesel-Affäre: Zwangsrückruf für Daimler". 22 June 2019.
  43. ^ Seythal, Thomas (24 September 2019). "German prosecutors fine Daimler almost $1 billion for breaking diesel rules". Reuters. Retrieved 24 September 2019.
  44. ^ "Kraftfahrt-Bundesamt schreitet seit über drei Jahren nicht gegen betrügerische Abgasreinigung bei Porsche und Audi Diesel-Limousinen und Diesel-SUVs ein". Deutsche Umwelthilfe e.V. (in German). Retrieved 2019-07-04.
  45. ^ Strauss, Marine; Hübner, Alexander (2021-07-08). "EU fines Volkswagen, BMW $1 bln for emissions cartel". Reuters. Retrieved 2022-01-28.
  46. ^ Welle (www.dw.com), Deutsche. "German authorities order BMW to recall 11,000 cars over diesel emissions | DW | 30.03.2018". DW.COM. Retrieved 2022-01-28.
  47. ^ Welle (www.dw.com), Deutsche. "BMW faces lawsuit in US over alleged emissions cheating | DW | 27.03.2018". DW.COM. Retrieved 2022-01-28.
  48. ^ a b c Plungis, Jeff (27 September 2015), "Carmakers cheating on emissions almost as old as pollution tests", Daily Herald, Bloomberg News
  49. ^ "Auto makers and EPA split victories on '73 vehicles", Chronicle-Telegram,  – via Newspaperarchive (subscription required), 22 January 1973
  50. ^ a b "Defeat Devices Must Go", The News Herald,  – via Newspaperarchive (subscription required), United Press International, 23 January 1973
  51. ^ a b "VW emissions 'defeat device' isn't the first". AutoWeek. 24 September 2015. Retrieved 26 September 2015.
  52. ^ a b Myers, Laura (1 December 1995), "Cadillacs Recalled To Remove Illegal Device", The Buffalo News, Buffalo, New York:  – via HighBeam (subscription required), Associated Press, archived from the original on 15 October 2015
  53. ^ Alexander, David E. (August 1998). "Clean Air Act Prohibits 'Defeat Devices' in Vehicles, Engines; Honda to Spend $267 Mil, Ford $7.8 Mil. to Settle Charges" (PDF) (Press release). United States Environmental Protection Agency.
  54. ^ a b c "Mack Trucks Diesel Engine Settlement" (Press release). United States Environmental Protection Agency. 22 October 1998.
  55. ^ "Dieselgate: the 28 agree to revise the Vehicle Licensing Act". The Brussels Times. 29 May 2017.
  56. ^ VW's Cheating Proves We Must Open Up the Internet of Things, Klint Finley, Wired, 24 September 2015.
  57. ^ "Volkswagen's Diesel Fraud Makes Critic of Secret Code a Prophet". The New York Times. 22 September 2015.