Smart fuel consumption

I wonder if you can give me some advice, last April I purchased a new Smart ForTwo CDi, primarily based on its published fuel economy of 85.6mpg, or 621 miles without stopping. I am deeply disappointed with the actual fuel consumption, currently averaging 63.1mpg, 26% less than published.

This has been calculated over 2,000 miles. The car has 9,088 miles on the clock so one would assume "run in", and I can just about get 400 miles without risking the reserve. I have written to the dealer principal at Mercedes Reading twice now without success. Do I have any legal right against the garage? I fully appreciate all car's will be factory tested in laboratory conditions but this is very misleading.

Asked on 15 January 2010 by RG, Stratfield Saye, Hampshire

Answered by Honest John
No. Because the 'official' figures are the result of prescribed tests laid down by the EC and are the only figures manufacturers are legally allowed to quote. (EC Directives 70/220, 94/12/EC, 96/69/ED, and 98/69/EC.)

Of course, almost every manufacturer electronically optimises its vehicles to do well in the certification tests because this puts the cars into a lower tax bracket. The fuel economy figures issued as a result of these tests bear little or no relation to what drivers can expect in real life. The EC law misleads.
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