Ford engineers have developed an ‘intelligent refuelling system’ to prevent petrol accidentally being put into the tank of a diesel-engined car.

Over 150,000 people a year put the wrong fuel into their vehicle and the figure is rising rapidly as diesel sales increase.

Misfueling leads to major fuel pump and high-pressure injection-system damage, along with engine component failure. Many insurance policies exclude misfuelling.

Ford’s "Easy Fuel" system consists of a sealed filler pipe insert and a fuel nozzle locator that guides the nozzle to the tank opening. The insert contains an automatic diameter detector that only allows the larger diesel fuel nozzles to be inserted into the filler pipe and locks out the thinner petrol nozzles.

Ford plans to introduce the "Easy Fuel" system into its product range within two years.