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Campaigns | Fuel claims

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Car makers deny manipulating fuel tests

7th October

We gave car makers seven days to tell us whether their fuel tests were misleading consumers. Almost all have now responded.

Car makers respond

Alongside more than 55,000 supporters, we’ve been piling pressure on the car industry in the aftermath of the VW emissions scandal.

Of the 17 manufacturers who have responded to us, the majority have said they don’t manipulate emissions and fuel economy tests. Subaru has not responded.

Redress for VW owners

Our executive director, Richard Lloyd, said:

‘It's reassuring that the majority of car manufacturers have explicitly denied rigging emissions and fuel economy tests. However, people will rightly be suspicious of these tests until an independent investigation has been carried out.

‘The Government must now be clear with consumers about the action it is taking, including real life testing and redress for people who have been misled.’

Car makers come clean

Are car makers manipulating fuel tests? Read their responses


‘The BMW Group does not manipulate or rig any emissions tests. We observe the legal requirements in each country and fulfill all local testing requirements.

‘We support the swift introduction of new regulations in Europe and beyond to ensure clarity, not only for consumers but also for the automotive industry.’

Daimler (Mercedes-Benz)

‘We categorically deny the accusation of manipulating emission tests regarding our vehicles. A defeat device, a function which illegitimately reduces emissions during testing, has never been and will never be used at Daimler.’

‘Mercedes-Benz emphatically supports the introduction of the WLTP (Worldwide Harmonised Light Vehicles Test Procedure).  This procedure is designed to supersede the New European Driving Cycle (NEDC), with the goal of bringing standardised and real-world consumption closer together.’


‘All Ford vehicles meet all applicable emissions requirements and do not have a so-called “defeat device”.

‘All our vehicles in Europe undergo emissions tests witnessed by the Type approval authorities and their technical services. We conduct all emission tests fully in line with regulations.’


‘Honda conducts business with a spirit, belief and commitment to abide by all laws and regulations without exception. Honda does not use any illegal software or defeat device.

‘A number of European authorities have recently proposed additional testing as a means to check for defeat devices, including potential on-road, real world testing. Honda supports this additional testing in order to help strengthen regulatory and consumer confidence.’


‘We confirm that none of our vehicles are fitted with any type of software intended to manipulate regulatory emissions tests results.

‘Hyundai Motor abides by the testing regulations and methods of each region where it sells cars including Europe.’

Jaguar Land Rover

‘Jaguar Land Rover does not use any emissions “defeat” devices or software.’

Kia Motors

‘Kia Motors confirm that none of its vehicles are fitted any type of software intended to manipulate regulatory emissions tests results. Kia Motors abides by the testing regulations and methods of each region where it sells cars - including Europe.’


‘In compliance with the law, Mazda works hard to ensure that every petrol and diesel engine it makes fully complies with the regulations of the countries in which they are sold. Mazda never uses illegal software or defeat devices. Customers can rest assured that their car is fully compliant with all regulations.’


‘Every gasoline and diesel engine that Mitsubishi Motors Corporation (MMC) manufactures fully complies with the regulations of the country in which it is sold.

‘MMC has never used software or other methods to illegitimately reduce emissions during testing in the gasoline engines, diesel engines, or plug-in hybrid systems which it develops. Our customers can rest assured that their vehicles fully comply with all applicable regulations.’


‘We can state unequivocally that we are committed to upholding the law and meeting regulations in all markets where we do business worldwide.

‘We can also confirm that Nissan does not employ ‘defeat devices’ in our products and complies with homologation procedures in all countries where it operates.’

PSA Peugeot Citroën

‘We respect the test procedures in place in all countries where we operate and our vehicles have never been fitted with software or systems to switch engines to a cleaner mode during emissions testing than in real driving conditions.’


‘Renault complies with all regulations and legislation for the markets in which it operates.

‘Our vehicles are not equipped with ‘defeat devices’ designed to alter the results of regulatory emissions tests.

‘Renault Group supports the implementation of European homologation tests representative of real conditions (Real Driving Emissions) which will better reflect laboratory test cycles.’


‘Suzuki Motor Corporation would like to confirm that none of its vehicles are fitted with any type of software or ‘defeat devices’ to manipulate regulatory emissions testing results.

‘Suzuki Motor Corporation abides with the correct procedures and testing regulations relating to emissions and Suzuki GB PLC would like to firmly reassure its customers and dealers of this.’


‘We confirm that no Toyota or Lexus models employ any kind of “defeat device” or “defeat strategy” intended to reduce the effectiveness of the emission control equipment.

‘We can also confirm that our emission control devices and strategies operate in exactly the same manner, regardless of whether our vehicles are being tested on a chassis dynamometer or driven on the road.’


‘General Motors designed software has no features that detect that a vehicle is undergoing emission test cycles. GM of course includes Opel and Vauxhall.

‘We would emphasise that GM has processes in place to proactively ensure robust emission compliance.

‘We know that there is a lot of discussion about moving from the current emissions testing to new, more stringent consumption tests (World Light Vehicle Test Procedure) and exhaust measurements on the roads (Real-world Driving Emissions regulation) to reduce the differences between the test bench and the roads in the future. We are an active participant here on all discussion levels and once the new regulations are in place, we will of course comply.’


‘Volvo Cars never has and never will fit any device to its cars that manipulates emission test results. Volvo engines have the same settings no matter whether they are being tested or in everyday use.

‘Volvo Cars believes the current testing regime for emission by diesel cars provides an industry standard that allows comparisons to be made between cars. That said, in partnership with the rest of the automotive industry, Volvo is working towards the design and implementation of new emission tests that better reflect everyday driving conditions.’


Government plans to launch investigation into vehicle emissions

The government today said that it planned to launch an investigation into vehicle emissions.

Our tests show eco cars are not as eco as they claim

Of all the cars we tested in 2012, the ultra-efficient small cars showed the greatest difference between our own mpg tests and the EU tests used by manufacturers.
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