Top 10: The worst carmakers for Real MPG

We’ve crunched the numbers of almost 120,000 Real MPG fuel reports to uncover the worst car manufacturers for real world economy. On average, a vehicle in Britain will miss its MPG target by 24 per cent, but some carmakers fair worse than others.

Click through the gallery below to discover which carmakers are the worst for Real MPG 

Listed: The car manufacturers that give best Real MPG

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Smart

Real MPG score: 78.6 per cent

Generally speaking, the newer the car, the worst the Real MPG. And few carmakers illustrate this better than Smart. Both the latest versions of the Forfour and Fortwo provide awful real world economy, while the older models are the polar opposite with some averaging at 92 per cent. 

Read more about Smart's Real MPG

Comments

bobvfr    on 31 March 2017

I think the emphasis on a percentage shortfall between 'advertised economy' and real world performance really shows the known shortcomings of the test process. [Or how good the manufacturers have become at taking advantage of the test process.]
I would have liked to see references to the actual mpg achieved. For example, my EcoBoost Fiesta actually gives a satisfactory [in my view] 45 mpg despite its poor rating.

Cabbage patch    on 31 March 2017

What a shame nobody will give mpg at constant speeds. Many decades ago one of the weekly mags produced a graph of mpg against speed. I remember that my twin choke webber Renault was worse at 30 mph than 40 while the then new BMW petrol injection was massively better at low speeds. If you drove at 50 on quiety country lanes the ranking order was quite different to motorway cruising.
If only we could have that info it would probably also show that at a constant motorway speed a lager engine might be better than a struggling economy model.
Please, somebody give us usefulk figures. Honest John's survey is a guide but Honda Jaqzz's pottering around at 30 mpg are likely to do better than repmobiles pushing down a motorway.

Doug S

Steve Mugglestone    on 1 April 2017

MPG is very dependant on how you drive and where you drive.
My Lexus IS 300h has never been on a motorway so 60mpg driving around North Yorkshire A/B roads is normal for me but anyone who does mainly motorway runs would be hard pressed to reach 50mpg.

Steve. M.

grumpy1    on 6 April 2017

I support Cabbage Patch's request for steady speed fuel consumption, which would provide useful additional information for drivers concerned about economy. I have just done a motorway journey of 150 miles at 55 to 60 mph in my S-Max, obtaining a computer readout of 55 mpg which compares well with my normal local driving figure of 29 mpg. I wonder what it would have been at 70 mph.

I would also like road tests to include mention of a car's top gear mph per 1,000 rpm, to provide an indication of fuel economy and noise on long runs

Stephen Lloyd    on 11 May 2017

Things are even worse than you might think. If you work out your mpg manually, then almost certainly you will find that your computer shows a considerably better figure.
For example, my Hyundai Mk 1 i20 usually shows around 47mpg, but worked out manually is around 42mpg.
I have seen similar discrepancies on previously owned cars.
This is something that requires further investigation!

Glynn K Brown    on 10 August 2017

I am amazed that anyone is surprised by his/her car supplying "overconfident" numbers. Speedometers have always given high readings. There's a law to allow it, i believe. My, so called, onboard computer tells me i can travel from Yorkshire to Bristol, in my VW Golf Plus 2.0 TDI, at 80+mpg. I know its wrong. I've always known it's wrong. But; A it makes me feel happy and B it gives me a useful relative comparison for other journeys. We should all know when we are being lied to. I just wish there were a way to fix it! Oh, yes. We're leaving the EU. That should do it!

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