Up to 150,000 drivers a year who fill up with the wrong type of fuel at the pumps and damage their cars may not be covered by their motor insurance.
The British Insurance Brokers' Association (Biba) says that putting the wrong type of fuel in a car can lead to more than £5,000 of damage. However, just 22 per cent of comprehensive motor insurance policies state that they will definitely pay out on claims where drivers have done this. At the same time, 40 per cent of insurers say they would not meet a claim for "misfuelling".
"Nobody goes out to put the wrong fuel in their car. If the motorist is innocent, the insurance industry would normally treat this as an accidental damage claim," said Graeme Trudgill, technical and corporate affairs executive at Biba.
"However, if the policy contains a misfuelling exclusion, then the motorist is unlikely to be able to claim at all."
Biba advises that if they do make a mistake of this kind, motorists should not start their vehicles and should notify the petrol station and a breakdown company immediately. The possibility exists that an insurer may refuse to pay out where a motorist has knowingly driven their vehicle with the wrong type of fuel in it, because the policyholder may be deemed to have failed in their duty of care.