Q. At a speed awareness course my husband was told that using the Sport setting on our automatic Mercedes in town saves petrol. My garage disagreed. Who is right?
RH, Christchurch, Dorset
A. Your garage. The Sport setting on any automatic makes the gearbox change up at a higher engine speed so you use more of the available power in each gear and can accelerate faster. In an economy mode (Mercedes calls it Comfort), gearchanges are made at lower engine speeds, using less power and saving fuel.
One reason for the confusion is that in economy mode some cars move away from rest in second gear, which can give the false impression that the engine is struggling and using more fuel.
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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