Warning over switch to lower-grade fuel

The Motor Industry Association (MIA) is urging motorists to resist the temptation to start using a lower grade of petrol in their vehicles in an effort to save money.

Its advice comes as fuel prices have recently hit record highs and there are warnings they may continue to increase for some time yet.

The MIA says owners of cars that require a higher grade of fuel – 95 or 98 octane – risk doing long-term damage to the vehicle’s engine if they use a lower grade of petrol than is recommended.

Mark Stockdale, principal technical adviser, explains: “Owners of cars that require higher octane petrol may be tempted to use 91 octane to save a few bucks, but it is a false economy. 

“If you use a lower grade than required, you risk damaging the engine which will cost far more than any saving in the price of fuel.

“Cars that require a higher-octane fuel are not designed to run on a lower grade, and major engine damage could result from regular use. The recommended octane rating is provided in the owners’ handbook, but if owners are not sure they could check with the dealer.”

He notes that about 20 per cent of new petrol cars sold require a minimum of 95 octane.