Almost one million cars, many from major manufacturers, are unable to use a new fuel which may soon be introduced to British forecourts.
Popular models from VW, Ford and Nissan are among the 868,000 cars which research suggests could be damaged by the use of E10 petrol.
The Department for Transport (DfT) is currently holding a consultation on proposals to encourage larger filling stations to stock the more environmentally-friendly fuel.
It uses 10 per cent bioethanol rather than the 5 per cent currently standard in this country. Higher bioethanol levels reduce the carbon output from burning the fuel.
Most affected models
- Volkswagen Golf (28,066)
- MG MGB (20,890)
- Mazda MX-5 (18,162)
- Nissan Micra (15,785)
- Morris Minor (12,796)
- Rover 25 (9,879)
- MG MGF (9,352)
- Ford Escort (8,947)
- Rover Mini (7,614)
- MG TF (7,568)
While most modern cars can run on the fuel, the research from the RAC Foundation shows that hundreds of thousands, including around 150,000 built after 2000, are incompatible with it.
Taking into account older cars being scrapped it estimates that by 2020, there will be 634,309 E10 incompatible cars on Britainâ€™s roads.
Among them are an estimated 28,000 VW Golfs, 18,000 Mazda MX-5s, 15,000 Nissan Micras and nearly 9,000 Ford Escorts.
Steve Gooding, director of the RAC Foundation, said that while some of the affected cars will be pampered classics many more will be low-cost daily drivers for families on low incomes.
He said: “As and when E10 appears on the forecourts, drivers need to know whether their cars can use it without being damaged.
“This analysis shows that even in a couple of years’ time there will still be hundreds of thousands of cars on our roads that are incompatible with the new fuel.
“Whilst some of the cars incompatible with E10 fuel will be historic models, many will be old but serviceable everyday run-arounds that people on a tight travel budget rely on to get about.
“The good news is both that the vast majority of cars on our roads are able to run on E10 and that Transport Secretary Chris Grayling has recognised the need to protect the users of those older vehicles which are not E10 compatible.
“It will be interesting to see whether the current consultation generates support for the Government’s proposed way forward.”
The DfT is proposing that if they choose to offer E10 petrol larger filling stations must also sell standard E5 to allow drivers of older vehicles to fuel their cars.
A DfT spokeswoman told PA: “This Government is ambitiously seeking to reduce the UK’s reliance on imported fossils fuels and cut carbon emissions from transport. But drivers of older vehicles should not be hit hard in the pocket as a result.
“The E10 petrol consultation will give a better understanding of the impact of E10 on the UK market, and to ensure that drivers are protected if any changes come into effect.”