Fleet News

Worst real world fuel economy performers revealed

Person using fuel pump in filling station

An independent test has found that 98% of cars could not match or beat official miles per gallon (mpg) figures with the Mitsubishi Outlander PHEV the worst performer.

Which? tested 200 new cars across 2013 and 2014 and found that all but three of them fell short of their official mpg figures, by 13% on average.

The Outlander PHEV's mpg was found to be overstated by 120%.

RAC Business spokesman Simon Peevers said: “Businesses will be rightly concerned that the mpg figures highlighted in these tests are so wide of the mark as it suggests the current procedure is clearly not reflective of real world driving.”

Research carried out during Q1 among 1,000 business decision-makers by RAC Business showed that fuel economy was the top priority when acquiring new vehicles for almost half, 44%, of those surveyed.

“That decision will be heavily influenced by the mpg stats issued by manufacturers and could even impact on budget forecasts for fuel if they can’t make the numbers, or anywhere near what’s been claimed,” continued Peevers.

“This is not good for either business drivers, fleet managers or the manufacturer and therefore needs to be rectified as soon as possible.”

The official test used by carmakers has been labelled outdated, with a number of loopholes that lead to unrealistic figures that don’t accurately reflect real-life scenarios, such as motorway driving.

For example, manufacturers can increase tyre pressures above the recommended levels to reduce rolling resistance.

However, the EU says it wants to replace it with a much more stringent procedure, which will better reflect real-world fuel economy figures, by 2017.

Which? executive director Richard Lloyd, said: “The new test should be brought in without delay so consumers are no longer misled by fantasy mpg figures."

Mitsubishi has responded to the findings, labelling the current test regime for emissions and fuel consumption "outdated".

Lance Bradley, managing director at Mitsubishi, said: "The current test regime does the industry no favours.”

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  • The Engineer - 23/04/2015 11:34

    I have a PHEV, only an idiot pays any attention to the official figures done over a few miles on a rolling road. I had already factored in the realistic fuel consumption. Still happy to be saving several thousand pounds in company car tax!

    • Simon - 23/04/2015 13:27

      I also drive a PHEV and agree with your comments, also 60+ mpg isn't bad for a large 4x4 car. The point of the article is to highlight the mpg test as not fit for purpose. With a hybrid car the availability of recharging facilities affects the real world mpg as much as anything

  • Darren - 23/04/2015 13:51

    I'm sorry but 120% difference between official figures and real world figures is criminal. I'm glad you guys are happy with your purchases and that you're saving money on company car tax, but imagine you didn't pay company car tax? If you were a private purchaser paying up to £40k for a car with figures like 148mpg being thrown around, and you drive it for a while and find that at best you can't even achieve half that, you're going to feel pretty ripped off. Especially when you consider you can by used soft roaders with MPG figures which are fairly close to that for £3k and up, £40k suddenly seems very poor value for money.

    • Bob the Engineer - 24/04/2015 19:08

      I don't agree Darren. The PHEV has been enormously popular with private purchasers like Motobility disabled drivers, many of whom only need to make lots of local journeys (within battery range) and are able to get incredible mpg, do you think they are ripped off getting HUNDREDS of mpg most the time?

      • Darren - 30/04/2015 13:40

        My father-in-law uses motobility vehicles and I can see where that would be a distinct advantage. His last car did less than 3000 in the three years he ran it. But as a motobility user, he didn't really own the vehicle, motobility did. Lets face it, most people don't by a car of this size and price to pop down the shops once a week, they want to actually drive the car for 12k+ miles per year. I really do believe that those customers would be the majority of private customers and yes, I think 67mpg for £40k when you are paying for a cat that you are promised does 140mpg is a huge ripoff

        • Darren - 30/04/2015 13:43

          Sorry, CAR, not cat! Sausage fingers!

  • Karl Watson - 23/04/2015 14:36

    I have been saying this for years, thank you FleetNews for putting some science behind my theory!

  • amd1 - 23/04/2015 15:25

    Regarding the replies above from 'The Engineer' and Simon, an interesting point following on from this is that if the mpg was being accurately measured then this would have a direct impact on the CO2 emissions and therefore the rate at which the vehicle is taxed as a company car: https://www.eta.co.uk/2010/02/22/calculating-a-cars-co2-emissions-from-its-mpg/ I agree that the official mpg is not an accurate representation of real world driving but to be that far out is almost bordering on fraud, especially when so much money is potentially avoiding HMRCs pot! ;-)

  • Paul - 23/04/2015 15:49

    At last someone is challenging the manufacturers! Why have trading standards not taken them to task already?

  • Buckets - 23/04/2015 17:45

    Another loophole example is that 4 wheel drive vehicles can take the test in 2 wheel drive with a propshaft disconnected thus reducing drag.

  • Starz - 23/04/2015 19:00

    However if you look at the table a different way then the Outlander actually came second best in actual mpg...3 mpg more than a Yaris but a much bigger car for carrying equipment and more comfortable on a long run

  • Mark S - 24/04/2015 06:52

    Tell me something that I didn't know ,I have been driving fleet cars since 1983 and I am sure that have never been anything like the rates quotes but since the HMRC rates it's now costing us !

  • Private motorist - 24/04/2015 09:13

    The manufacturers mpg figures are all on the same basis, in a building with minimal load, on a rolling road (presumably low resistance), no weather implications. As such they are comparable against each other. However 'real world' driving varies dramatically, due to life impacting the driving in terms of loading on the car, actual weather conditions, quality of fuel and lubricants, driving styles and so on. I am a private motorist and have been for over 40 years. The figures are a guide that need to be discounted by about one third. Yes there will be exceptions, but that is what they are. My real world mpg varies with my wife's and my sons real world mpg figures over the same route by almost 10 mpg. Go figure!

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