Yes, cheat devices have been found in diesel cars in the UK. The issue came to light during the diesel emissions scandal, commonly referred to as "Dieselgate," which began in 2015 when Volkswagen admitted to installing such devices in 11 million of its vehicles worldwide.

These devices could detect when a vehicle was undergoing emissions testing and would adjust the engine's performance to reduce emissions during the test. However, under normal driving conditions, these cars would emit pollutants far above the legal limit.

Of the affected Volkswagen cars, it was estimated that about 1.2 million were in the UK. Also included within these 1.2 million vehicles were cars within the VW brand - Audi, Seat, and Skoda, as well as VW commercial vehicles. Since then, other car manufacturers have also been under scrutiny for potentially using similar tactics.

Massive car companies like Mercedes, Ford, BMW, Vauxhall, Nissan, and Renault are all being caught up in Dieselgate, and many more are being investigated. All of these car companies will have sold affected vehicles in the UK.

Various legal actions have been initiated against these manufacturers, both in the UK and internationally. Many owners of affected vehicles in the UK have been able to file claims for compensation as a result. Diesel car owners who believe they may have been affected are encouraged to check their eligibility for making a claim.

Several car manufacturers have admitted to the use of cheat devices and have faced significant fines and lawsuits as a result. Volkswagen, for instance, admitted in 2015 to installing cheat devices in millions of their diesel vehicles worldwide.

However, not all manufacturers accused of using cheat devices have admitted guilt. Some continue to deny the allegations and argue that the technology in question is not designed to deceive emissions tests but is necessary for the proper function and protection of the engine. These manufacturers often assert that their vehicles comply with the regulations as they were understood at the time.

Claims against manufacturers are often complicated legal battles that can take years to resolve due to the technical nature of the allegations and the need for extensive investigation. However, the trend in many countries across the world has been towards holding manufacturers accountable for misrepresenting the environmental impact of their vehicles.

In the UK, the Dieselgate scandal has had a significant impact and has led to numerous legal actions.

The scandal broke in September 2015 when the US Environmental Protection Agency (EPA) discovered that Volkswagen had installed software in its diesel cars to cheat emissions tests. The software could detect when the vehicle was being tested and change the car's performance to pass the test. In real-world driving conditions, however, the cars emitted far more nitrogen oxides (NOx) than permitted by law.

Volkswagen admitted that 11 million cars worldwide were fitted with this "defeat device" software, with an estimated 1.2 million of those affected vehicles being in the UK.

In response, the UK government launched an inquiry, and Volkswagen pledged to recall and fix affected cars. However, reports suggest that some fixed vehicles experienced mechanical problems afterward.

The scandal has resulted in a significant loss of trust in Volkswagen and other manufacturers. In the UK, several legal firms launched lawsuits against Volkswagen on behalf of affected car owners seeking compensation. The scandal also sparked increased scrutiny of diesel emissions and vehicle testing procedures in general, leading to stricter emission standards and testing methods.

Moreover, it has led to a broader societal discussion about diesel vehicles and their environmental impact, with many cities in the UK and Europe considering or implementing bans on older diesel cars.

Diesel claims typically fall under broader legal principles such as consumer protection laws, tort law, and contract law.

For example, under the UK Consumer Protection from Unfair Trading Regulations 2008, it is unlawful for a trader to engage in unfair commercial practices towards consumers. If a car manufacturer knowingly sold cars with emissions-cheating software, this could be seen as a misleading action that gives rise to a right to claim.

Moreover, under contract law, if a car was sold on the basis of specific claims (e.g., that it complied with emission standards), and these claims were not true, there may be a claim for breach of contract.

In terms of tort law, consumers may have a claim in the tort of deceit if they can prove that the manufacturers intentionally made false representations (e.g., regarding the level of emissions), which caused them to suffer a loss.

The Dieselgate scandal has prompted a wave of group litigation orders (GLOs) in the UK – a type of class action that allows multiple claimants with common or related issues to join together in a single legal action. In April 2020, in a landmark GLO, the High Court in London ruled that Volkswagen had installed illegal "defeat devices" in thousands of its diesel vehicles.

These legal principles and the landmark case represent the basis for the legal arguments in most diesel emission claims in the UK. For the most recent updates or for advice on specific circumstances, individuals should consult with a legal professional specializing in diesel emissions claims.

Please note: The above does not constitute legal or financial advice and is provided for general information purposes only. No warranty, whether express or implied is given in relation to such materials. Emissions.co.uk shall not be liable for any technical, editorial, typographical or other errors or omissions within the information provided.