Q. When our VW Golf had a recent service, the garage found a minor problem with erratic acceleration. The technicians asked us where we bought our fuel and, when we said we got it from the local supermarket, advised us to go elsewhere. I remember concerns about supermarket fuel in the past but thought any problems had been rectified. Does the fuel on British forecourts have to meet any kind of standard?
GS, Upwood, Cambridgeshire
A. All fuel sold in the UK must meet a European standard for quality — EN228 for petrol and EN590 for diesel. This applies to supermarkets as well as branded fuel stations.
In fact, most supermarkets buy their fuel from companies such as Harvest Energy and Greenergy, which also supply many branded filling stations. The only difference is likely to be the additives that each company adds to its fuel. There is no official requirement to add cleaning agents or any other chemicals, although most sellers do. The Volkswagen Group told us it does not advise owners of any of its cars to avoid supermarket fuels.
Your garage’s suspicions may date back to the 1990s, when supermarkets first began selling fuel and had to meet the European standard of the time. There were suspicions then that they were keeping prices down by buying lower-quality (though still up to standard) fuel, which left hard deposits on the fuel injection components, and by not including any detergent to get rid of the deposits. These fears were based on anecdotal evidence and are not thought to have been substantiated.
Any engine using standard filling-station fuel can start to run badly or become reluctant to start if deposits accumulate, especially if the car is used for a lot of short journeys. If so, it is worth switching to one of the “premium” fuels — Shell V-Power, Tesco M omentum99, BP Ultimate, Total Excellium, Esso Supreme — for two to three tankfuls. These contain powerful agents that will clean the fuel system of your car. Their claims about improved fuel efficiency and so on are less clear-cut.
TIM’LL FIX IT
Tim Shallcross used to train AA patrols to fix cars. Now he advises the Institute of Advanced Motoring – read more from Tim here.
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