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Volkswagens designed to cheat emissions tests

The US Environmental Protection Agency (EPA) has said that Volkswagen had installed illegal software – a device designed to reduce emissions of nitrogen oxides (NOx) – to cheat emissions tests, allowing its diesel cars to produce up to 40 times more pollution than allowed.

The US government has ordered VW to recall 482,000 four-cylinder VW and Audi diesel cars including the Audi A3 and the VW Jetta, Beetle, Golf and Passat models produced since 2009. SEAT and Skoda cars worldwide could also be involved in the issue.

How did Volkswagen cheat emissions tests?

The EPA has said that the engines had computer software that could sense test scenarios by monitoring speed, engine operation, air pressure and even the position of the steering wheel. When the cars were operating under controlled laboratory conditions – which typically involved putting them on a stationary test rig – the device appears to have put the vehicle into a safety mode in which the engine ran below normal power and performance. Once on the road, the engines switched from this test mode. The result is that the engines cheat emissions tests by emitting nitrogen oxide pollutants up to 40 times above what is allowed in the US.

VW must recall all the cars, remove the defeat device and improve the cars’ NOx emissions, which creates smog and has been linked to increased asthma attacks and other respiratory illnesses.

The EPA said that the fine for each vehicle that did not comply with federal clean air rules would be up to $37,500 (£24,000). With 482,000 cars sold since 2008 involved in the allegations, it means the fines could reach $18bn.

VW has admitted that about 11 million cars worldwide are fitted with the so-called “defeat device”. It said it was setting aside €6.5bn (£4.7bn) to cover costs of the scandal.

About €25bn, or a third, was wiped off the value of Volkswagen’s shares in the two days of trading since the scandal erupted, and the volatility is continuing. The news also knocked billions of pounds off the value of other carmakers amid concern that rigging emissions tests is common across the industry.

The EPA said “A sophisticated software algorithm on certain Volkswagen vehicles detects when the car is undergoing official emissions testing, and turns full emissions controls on only during the test. The effectiveness of these vehicles’ pollution emissions control devices is greatly reduced during all normal driving situations. This results in cars that meet emissions standards in the laboratory or testing station, but during normal operation, emit nitrogen oxides, or NOx, at up to 40 times the standard.”

British carmakers said that there was no evidence of manufacturers attempting to cheat the European system, but agreed that the system of testing needed reform.

Mike Hawes, the chief executive of the UK Society of Motor Manufacturers and Traders, said: “The EU operates a fundamentally different system to the US, with all European tests performed in strict conditions as required by EU law and witnessed by a government-appointed independent approval agency. There is no evidence that manufacturers cheat the cycle. Vehicles are removed from the production line randomly and must be standard production models, certified by the relevant authority – the UK body being the Vehicle Certification Agency, which is responsible to the Department for Transport.

“The industry acknowledges, however, that the current test method is outdated and is seeking agreement from the European Commission for a new emissions test that embraces new testing technologies and is more representative of on-road conditions.”

BEUC, the European Consumer Organisation, is calling for a full investigation into EU vehicle emissions and fuel consumption testing.

BEUC’s Italian member organisation Altroconsumo performed vehicle tests on a Volkswagen Golf last year. Their results showed fuel consumption levels 50% higher than the figures officially declared by Volkswagen indicating that owners could be spending as much as €502 per year more on fuel consumption than expected from the company’s advertisements. A collective action against VW was launched earlier this year and is expected to be seen before a court in Venice next month.

Monique Goyens, Director General of BEUC, The European Consumer Organisations said: “We’ve been saying long before this scandal broke out that one of the problems in the EU, unlike in the US, is the absence of a surveillance system which would require independent on-the-road testing. The EU needs to implement such a system to restore trust amongst consumers in emissions and fuel consumption test programmes.

“We also need to see a full investigation conducted by the European Commission into the use of these ‘defeat devises’ to see if car makers in Europe have also made use of them – and not just for air pollution but for fuel consumption testing too.

“It is essential that the EU starts work on developing a robust on-road vehicle test procedure which could do away with the need for laboratory fuel consumption and CO2 emissions testing. The fact of the matter is that EU vehicle emissions and fuel consumption testing has been broken for a long time and consumers are desperate for a better system.”

Tim Barlow, Air Quality expert at TRL (the UK’s Transport Research Laboratory), comments:

“The Volkswagen emission scandal has put the spotlight on vehicle emission testing not just in the US, but globally. The full extent of the problem is not yet known, but if similar practices are taking place in the UK, then this could well have contributed to the current air quality problem we’re facing.

“NOx emissions should not be taken lightly. Aside from helping to form smog, they also have a serious health effects; including contributing to the development of respiratory and lung diseases and cancer. So we need to ensure that all steps are taken to reduce emissions where possible and meet stringent targets.

“What the issue has done is to bring to the forefront the need for changes to existing test procedures. Current testing methods are outdated and offer room for error or optimisation, so it’s imperative that industry, governments and regulatory bodies work together to find the best way forward. Ideally we need to move towards a testing model that’s based on real driving emissions, carried out with vehicles operated on normal roads. This should be followed up with in-use compliance testing, whereby a sample of vehicles already in use are tested to check they still comply with the emissions limits.

“TRL will be actively engaging to ensure that an independent, evidence based perspective is a core part of any decisions made to encourage change. If we are able to agree and adopt a unified solution to the problem, then we could see an improvement in air quality, both in the US and Europe.”

A Green Car Guide visitor recently took Volkswagen to court for her Golf BlueMotion diesel not meeting its claimed miles per gallon figure: read more.

Green Car Guide has been reporting on real-life miles per gallon of the cars that it tests since 2006. Miles per gallon relates more directly to CO2 emissions rather than to nitrogen oxides (NOx) emissions, however in real-life driving, on average, the cars we test deliver economy that is typically 20-25% less than the official figures. The ‘greener’ cars – such as diesel-electric hybrids – can have some of the worst discrepancies. The best performers in terms of real-life miles per gallon – in real-life driving such as on motorways at 70mph – are generally diesel cars that also have good aerodynamics.

The official combined miles per gallon – and CO2 emissions – figures for plug-in hybrids are the most misleading, as the figures are based on the short and low-load NEDC test. If all your driving matches the NEDC testing cycle, with your car being fully recharged before each journey, then you may come close to the NEDC figure. However this is highly unlikely, and therefore most motorists will never enjoy anything close to the official economy figures quoted.

As an example, the Mitsubishi Outlander PHEV has been a huge sales success in the UK, offering the promise of 148mpg, 44g/km CO2 emissions, and very low benefit in kind company car tax of just 5%. A large plug-in hybrid 4×4 SUV at a competitive price of around £28,000 after the UK government plug-in car grant is a welcome addition for consumers, and if you can carry out most of your journeys on electric power, with occasional longer journeys using petrol power, then the car makes sense, and will reward its owner with good fuel economy and low petrol bills. However if the car is used primarily for long distances then it is a large, heavy petrol 4×4 and it would be easy to average real-life economy in the mid-30’s miles per gallon.

In summary, the NEDC test needs updating as soon as possible, and especially for plug-in hybrids.

Paul Clarke


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