In 1998 the European Commission and the motor manufactures set out a binding goal to reduce co2 emissions and MPG by 25% by 2008/9, bringing the average co2/km to 130. This was further renewed in 2009 to reduce it further, and by 2020 to have an average fleet co2 emissions of just 95g co2/km.

This is measured by averaging out the type of cars sold by each manufacturer and each cars co2 emissions. The co2 emissions in turn are measured using a standard EU test procedure, giving a reading for every car on sale in Europe today.

After a few years the manufactured started using tricks to improve the MPG in the tests to the point today where the EU figures are completely misleading.  They do not represent the real world.  Some of the tricks they use in the test include, apparently, is to disconnect the alternator, tape up cracks in the bodywork to improve airflow, remove wing mirrors(!), disconnect the brakes to reduce friction and  use special oils in the engine to improve efficiency.   All of these tricks help to improve the MPG figures, bring down the manufacturers co2 average and help meet EU targets.

The introduction of Stop/Start systems in the cars is a classic example of  manufacturers bringing in technology to help reduce the stated MPG, but which have very little real world benefit.

Another sign has been the move towards smaller turbo charged petrol engines which has been evident in the last few years, but from my experience they are not much more economical than the previous engines, in the real world, despite their much improved MPG figures in EU tests.  The drive of these engines is also completely different from the older engines, with a complete lack of torque until the turbo kicks in - if you are thinking of buying one  a test drive is completely necessary to see if it suits your driving style.   

The one good thing about this move is the smaller tax than previous generation engines.  It is not uncommon to see even larger  cars now have £20 or even zero tax for the year.  This is probably the greatest benefit from the last few years but don't expect your new car to have vastly better fuel economy than a similar previous model, even if the book tells you it will.

So are the manufactures lying with MPG? I would argue no, as they are statistically correct, but you need to know to disregard them and take them with a large proverbial pinch of salt when deciding which car to buy.

If the salesman says you should have no problem getting the 80 mpg stated in the book - challenge him to show you on a test drive and watch his face drop!

For help and advice on buying and selling cars drop me a line 

Nigel Speers


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