Tesco, Sainsbury's, Asda, Morrisons and other drivers warned over new E10 fuel

A major new fuel could "worsen pre-existing conditions" with drivers warned of "less efficient" vehicles. Motorists at Tesco, Sainsbury's, Asda, Morrisons and other forecourts are being cautioned about a common fuel found at all forecourts which could significantly affect the health of their vehicles.

Experts are now cautioning that E10 fuel - first introduced three years ago - might damage the internal workings of vehicles, especially older models. Darren Miller, from BigWantsYourCar.com, has spoken out despite the fuel's lower cost.

He cautioned: "It's performance in cars with smaller engines could also be less efficient, as some reports suggest it falls short of E5's efficiency. For those with vintage vehicles, caution is advised when considering E10 fuel due to its increased ethanol content, which could worsen pre-existing conditions in older engines.

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"Over time, engines can accumulate carbon, which might increase compression pressures and cause knocking or pinging." Before E10's introduction, the standard unleaded petrol was E5, comprising 95% regular unleaded petrol and 5% renewable ethanol hence the name, reports Birmingham Live.

Most petrol cars made since the 1990s can run on E10 fuel without problems, but there were some exceptions particularly in the early 2000s. E10 can affect older cars in several ways, including causing cold start issues and vapour lock.

Ethanol's increased volatility can lead to vapour lock (where petrol turns into gas) during high operating temperatures, resulting in stalling. Its high solvency can also cause issues with various seal and gasket materials used in fuel systems, as well as with glassfibre resins.

In addition to the risk of fuel leaks, rubbers and resins can partially dissolve, creating deposits that could block carburettor jets. Furthermore, ethanol can become acidic and corrode aluminium, zinc and galvanised materials, along with brass, copper and steels coated in lead or tin.

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