Volkswagen has started to fix more of the cars affected by its emissions scandal in the UK.
The emissions scandal has been in the news since September last year, when details first surfaced about a 'defeat device' that could cheat emissions tests worldwide.
But what actually happened and what does it mean for owners of affected cars? Here's what you need to know.
Officials in the United States uncovered software in certain models of Volkswagen and Audis, designed to beat the strict NOx particulate emissions and air quality tests used in the USA.
Volkswagen's so-called 'defeat device' was first discovered in September last year and is seen as a cheat, rather than a solution, to NOx emissions. It has since been discovered that the same defeat device is present on cars sold in Europe and the UK, and that it has also been used to artifically alter the results of emissions tests.
Since then, it was found that models sold by Skoda and Seat - both part of the wider VW Group - were also affected.
What is the problem?
The way the cars perform in day to day driving is not affected. The issue only relates to when the car’s emissions are tested; the car detects it is being tested and the engine switches to a different mode to artificially lower the emissions and ensure the tests are passed. Therefore, the tests are not indicative of the car’s particulate emissions in the real world.
What models are affected?
Globally, 11m cars have the software to cheat the tests fitted. They have a 1.2-litre, 1.6-litre or 2.0-litre diesel engine with the designation EA189. In the UK, this is the breakdown of how many models from each brand are affected:
Volkswagen passenger cars 508,276
Volkswagen commercial vehicles 79,838
Volkswagen has also confirmed that five million of its cars are affected worldwide, while Audi has said that a total of 2.1 million of its cars worldwide are also involved in the scandal - with 1.42 million of those cars residing in Western Europe. Skoda has said that 1.2 million of its cars are involved in the scandal, along with 700,000 cars from Seat.
Around 4000 new cars that were on sale at UK VW, Audi, Skoda and Seat dealerships have been taken off the stock list.
Does it affect fuel economy?
The investigation is not about emissions of CO2 and therefore fuel economy. It specifically relates to particulate emissions, which affect air quality in city centres.
Inaccurate or misleading official fuel economy figures are a separate issue - and a result of the European Union's laboratory-based tests. The VW scandal appears to have prompted politicians into fresh action to revamp those tests to make them more relevant to real-world driving.
Will I get compensation?
Volkswagen recently announced that affected owners in the US would receive up to around £7500 in compensation.
However, Volkswagen bosses have said that no compensation in Europe will be offered, because affected owners in the US could find their cars have reduced fuel economy after the fix is applied. European cars are said to be unaffected after the fix, but the government's Transport Select Committee has called this "deeply unfair" in a recent report.
Volkswagen UK has responded by saying that it will continue to roll out its proposed fix on affected cars free of charge. A statement read: "At Volkswagen our customers are our priority, and so we are working hard to deliver technical measures for the affected vehicles in the UK.
"We have contacted all affected customers, with around 200,000 now informed that their model should be brought into their nearest retailer to receive the technical measures, which take between 30 and 60 minutes of workshop time, according to model, and of course are free of charge.
"Close to 50,000 vehicles in the UK have now received the technical measure, a number which will continue to increase as further vehicles’ technical measures are developed, rigorously tested and then approved by the relevant transport authorities."
What do I need to do?
If you own a car that's affected by the emissions scandal, you will have already been notified and VW will advise as to when you can bring it in to a dealer to receive a fix. The first recalls started earlier this year, and the work will be carried out free of charge.
Volkswagen originally set itself the target of having all the corrective work completed by the end of this year, but officials have since said the recalls could go into 2017.
The VW Group also has websites that allows UK owners to type in their car's Vehicle Identification Number (VIN) and see if it is affected by the 'defeat device' software. You can access the VW site here and a similar service for Audi cars here. VIN checking sites for Skoda and Seat are also live. Skoda's is here and Seat's is here.
The latest fix concerns VW's 1.2-litre TDI diesel engine, which is found in the VW Polo, Seat Ibiza and Skoda Fabia. This recall affects over 18,000 VW cars in the UK, and the owners of the affected vehicles should expect to be contacted very soon. The proposed fix does not affect the fuel consumption, performance or noise of the engine.
Fixes for some of the cars using VW's EA189 2.0 TDI engines, including those found in the Passat and Passat CC and the Golf Bluemotion, have already been approved, while a fix for the EA189 1.6 TDI engine is still awaiting approval. It's worth noting that if you're buying a new car it won't be affected, as the latest generations of these cars use newer generations of engines.
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