/ Money, Motoring

Are misleading fuel consumption claims costing you money?

Imagine this. In your hallway sits a huge box containing a new TV. You’re excited; it’s the 50-inch model you’ve had your eye on for ages. But when you open the box, it’s no bigger than your old 32-inch set.

You check the label. It’s the right model. You look at the manufacturer’s website: ‘50-inch screen’ it says. So you call the retailer – there must be a mix-up.

No, they say. The TV is officially a 50-inch model, it’s just that the industry measures inches differently to normal people. You’d be outraged, wouldn’t you?

Readers feel let down on fuel economy

But this ridiculous situation isn’t so different to what’s happening all over Europe when people buy a new car.

They read the official miles-per-gallon (mpg) figures stated in ads and plastered over manufacturers’ websites, then find the car delivers a fraction of the miles expected per tank.

The reason? An outdated official, European Union-approved mpg test – in effect, the ruler has its inches marked all wrong.

We’ve touched on this subject a couple of times this year – first in April then again in May – and those articles prompted almost 200 comments, many from readers who’ve been disappointed with their car’s fuel economy.

Then, last week, we were contacted by Ron Nicholls who bought a new Nissan Qashqai in December 2014.

Like having to put an extra £20’s worth in the tank each time

Ron’s car, the 1.2-litre petrol version, achieved an impressive 42.8mpg in the ‘urban cycle’ of the official test, yet Ron averages just 28.8mpg driving around town.

That’s a third less than he expected. As he put it, that’s like having to put an extra £20 of fuel in the tank each time he fills up. The Qashqai also failed to live up to its mpg claims in our test.

Ron feels he was misled by the official mpg figures, but despite trying to engage with Nissan he has, in his words, ‘been given the brush-off’.

Manufacturers are required by law to publish mpg figures generated by the EC’s flawed, out-of-date official mpg test. But to conform with Advertising Standards Authority guidelines, they’re also supposed to make it clear that ‘MPG figures are obtained from laboratory testing and intended for comparisons between vehicles and may not reflect real driving results’.

We checked Nissan’s website and found it’s almost impossible to find such a caveat. In the downloadable brochure it simply states figures are ‘in accordance with 1999/100/EC’ and ‘Technical data subject to final homologation results’. Do you think that’s clear enough?

What do you think? Are manufacturers misleading us when it comes to fuel economy? Should they do more to make it clear how many mpg we’re really likely to get?


It is well established that the current NEDC fuel consumption test is out of date, but some of our car manufacturers are doing their best to delay the introduction of the new WLTP test: http://www.raccars.co.uk/news/article/3305/european-car-makers-delaying-real-world-mgp-tests

What concerns me more is the fact that manufacturers do their own fuel consumption tests rather than having the job done by independent test laboratories. Rather than testing a car straight from the showroom, various modifications are carried out to produce artificially high fuel economy figures. These can include taping up door seals, over-inflating tyres, changing the grade of oil, disconnecting the alternator, fiddling with the brakes and removing seats to decrease weight. Thank goodness Which? adopts a more sensible attitude to product testing. As I understand it, all products tested for Which? are purchased rather than submitted by manufacturers for testing.

When I bought my present car, I enquired about the fuel consumption and was quoted the manufacturer’s figures without any reference to the fact that they would not be achieved in practice.

Even if the WLTP test is delayed, there is no reason why modification of vehicles prior to testing should not be stopped promptly.

Most of us are all too aware of misrepresentation and broadband speeds have been discussed at length on Which? Conversation. Suppliers are allowed to quote ‘up to’ speeds even if only 10% of customers can achieve them. Why is honesty such an alien concept in the marketing of products to the general public?

Les spiller says:
27 July 2015

I must admit iam well pleased with the fuel consumption on my Vauxhall Mokka 1.6, I purchased the car brand new ,I get well over 410 -420 miles per tank which is pretty good when that includes town and motorway driving.

Alex Mcil says:
18 January 2016

Hello Wavechange,
You do make some very valid points there, especially the last sentence you have mentioned.
I have to say that although the WLTP will be a far better test, there is still concerns that because it too is very much a lab test, that there will still be discrepancies between the test and real world driving.

The NEDC shows cars being 35-40% more efficient than in real life. It is estimated that the WLTP will greatly reduce that figure to about 23%, but the question is, is that enough? It is also believed that in the passing years, that 23% figure will only increase.

What I cannot understand is, why cannot these tests be done on the road or a standardized track that simulates real world driving. Surely having the vehicle pull its own weight, taking corners, taking on hills, braking etc would solve much of these legal cheats……on thing seems for sure, VW’s software would not have work if their cars were actually tested on the road……….all very interesting stuff.

[This comment has been tweaked to remove a URL in line with our Community Guidelines. Thanks, mods]



Perhaps Nic you should look at Which?’s attitude to washing machine as in August 2013 it said 8 out of 12 washing machines got nowhere near a 60C wash but this was OK as 60C did not mean what it said as a temperature but was an indication that the wash cycle delivered equivalent optical cleanliness to 60C wash.

The lowest wash cycle was at 41C.

Knowing this Which? chooses not to publish the heat profiles for 60C washes. This may seem unimportant to some but in the UK over a third of nursing staff wash their uniforms at home – and a proper high temperature wash is required. Which? not mentioning these machines 60C faux temperature is a crime.

” Nearly half of hospital uniforms are washed in temperatures too cool to kill bacteria, says DMU research

De Montfort University Leicester (DMU) researchers have recommended there should be national guidelines set for washing uniforms of nurses and other hospital staff after it was revealed 49 per cent of those surveyed did not use water hot enough at home to kill off certain bacteria.
– See more at: http://www.dmu.ac.uk/about-dmu/news/2015/march/nearly-half-of-hospital-uniforms-are-washed-in-temperatures-too-cool-to-kill-bacteria,-says-dmu-research.aspx#sthash.Ns1uHO2L.dpuf


Thanks for your comment Diesel. Although I can see the connection, let’s stick to talking about cars and MPG claims on this particular Convo.


Actually Patrick I think dieseltaylor’s comment is to the point. I don’t think your “similar example” of the size of a TV screen is very good. Car fuel consumption and even washing machine temperatures are far less tangible things than TV screen size, and “which” elected not to make such a big deal of variable washing machine temperatures.

Now whilst agreeing car manufacturers consumption figures tend to be wildly optimistic we must remember there is a standard procedure to determine such figures and manufacturers want to sell cars so they’ll use every trick they can to make the numbers look good, and they all do it.

Most people realise that in the real world things are very different and the final fuel consumption achieved can vary greatly because of myriad factors. Bet if you or perhaps a selection of people drove the same car the same say 50 mile route at different times of the day, in different weathers and perhaps at different times of the year, the fuel consumption figures would vary greatly.
To expect a manufacturer to give figures you can expect come hell or high water is unrealistic.

However I would agree the standard test really needs to change to show more “achievable” consumption figures. But even with things as they currently are figures given still enable a comparison model to model even if the mpg figures for all are very optimistic.
Now really we’ve all already really known this to be the case for many years, haven’t we?
Just like not all washing powders really wash whiter than white, and not everything does exactly what it says on the tin unless if perfectly used in perfect conditions.

If “Which” wants to do something useful campaign to get the standard fuel consumption test changed to something more realistic, but even then it will at best still be an approximation and a very different animal to the size of a TV screen.


Chris, If you watch the Youtube video from an Aussie Auto Expert (see my post below) and take his advice you simply add 30% on to the figure given to you by the dealer to achieve a realist figure 🙂


Chris wrote: “Now whilst agreeing car manufacturers consumption figures tend to be wildly optimistic we must remember there is a standard procedure to determine such figures and manufacturers want to sell cars so they’ll use every trick they can to make the numbers look good, and they all do it.”

That is my fear and why I strongly support independent testing. Wherever money is involved there is the risk of companies trying to make out that their goods and services are better than they are.


The blame for the main disparity between “real life” mpg and the figures the manufacturers are obliged to publish (and only those figures) lies with the EU in requiring an out of date and poorly-specified test regime. So the bulk of the blame must be put at the EU’s door.

If you want an idea of real life figures then there are a number of websites – Honest John, Which, for example. We should ensure these are widely published to prospective buyers – it is information that they want.

We should find out exactly why the revised test (which is admitted by all that it will still not give real life figures) is being delayed. The major focus of the test is on reducing CO2 emissions and this can bring with it a heavy cost. It may be that cost effective technology is not yet ready or it may be that EU emission requirements are more stringent than in other markets. Someone should find out the facts before assuming one party or another may be deliberately holding things up.


Here is a damning report about the car industry, from European consumer organisation BEUC:



“In your hallway sits a huge box containing a new TV. You’re excited; it’s the 50-inch model you’ve had your eye on for ages. But when you open the box, it’s no bigger than your old 32-inch set.”
I wish Which? would stop using these kind of silly examples when introducing a serious topic, and, instead, put forward facts and information. I’m sure those who subscribe to these conversations don’t need such hype to stir them into making thoughtful contributions.

Out of interest, the average reported real life mpg is 86% of the EU figure, according to one source. The 32″ TV picture size is 41% of the 50″. Ron’s urban mpg (and we’ve no idea how he drives) is 68% of the EU figure. So where’s any sensible comparison here?


I am not too concerned about the ‘silly examples’ used by Which? They are used to draw attention to real problems.

What concerns me more is that car manufacturers modify their cars to produce higher fuel economy figures. That’s more than silly – it is dishonest. No one should condone the practice. When are manufacturers going to behave sensibly and responsibly?


wavechange, the problem with inaccurate statements from an organisation such as Which? is that they gain publicity in a misleading way – in that the facts behind the argument do not reach the reader to allpow them to decide what the “real problem” is.. One or two examples recently. And as many conversations show, we don’t like misleading things, do we (or is Which? an exception?).

This is not the way, in my opinion, for what should be a reputable fact-based organisation to behave. I’ll leave that to politicians, because we always take what they say with a large pinch of salt. But Which? should be more objective and responsible.


Malcolm – Which? has been drawing our attention to a long standing problem that manufacturers’ fuel economy figures are not very useful to consumers. In the absence of the motor industry getting its act together, Which? has designed its own tests that are carried out under standard conditions but probably give a more useful indication of what drivers might expect to achieve.

To the best of my knowledge, it is the manufacturers that are wanting to delay the introduction of the WLTP test. If there is evidence that they have been pleading for it to be implemented at the earliest opportunity, I would be interested to read about this.

What possible justification is there for any manufacturer modifying a car to perform better in any test? I’m not a lawyer but I regard it as fraud, on a grand scale. As I see it, Which? are simply alerting us to problems. I have not noticed many apologies for false statements or successful prosecutions for libel in the time I’ve been subscribing.

Let’s have fuel economy figures that are useful to motorists, bearing in mind that no figures are ever going to replicate how different people drive and other relevant factors.


wavechange, these are essentially fuel economy figures from a defective EU test regime that the manufacturers must publish, so let’s aim the criticism appropriately. Whilst the leeway given in the EU tests are adding to the disparity, they are not the most significant factor. I simply want to keep the focus on the real problem, not the emotive one.

“Real life” figures that are more useful to drivers have been available for many years. Pointing people to where they are publicised is a far more positive approach.

We are airing old arguments, so perhaps move on?


Malcolm – You can do what you wish, but I would like to stick to emotive discussion, which has received little focus in the Conversation introductions about fuel economy. Why should another consumer organisation refer to “The Great Fuel Consumption Scam” when Which? sanitises the problem with a title such as: “Are misleading fuel consumption claims costing you money?”

I would like to find out where manufacturers are officially told that they can tape up the doors, over-inflate the tyres, etc., etc. to produce better fuel economy figures. If the regulations don’t allow for that, why should any company do these things unless they are are setting out to cheat the public?


Just because BEUC chooses a more inflammatory headline than Which?does not make it any more authoritative.

The case still comes down to the EU imposition of their outdated NEDC (the test cycle manufacturers must use to determine their car emissions). The information I have come across (but someone may have better information) is that whilst the NEDC test has leeways that allow manufacturers to make modifications to improve their emissions these do not result in the most significant part of the difference between “official” mpg and “real life” mpg. That is down to test cycle as specified.


Malcolm – You still have not explained why manufacturers are modifying their cars to achieve higher fuel economy figures. I presume therefore that they are not instructed to do this. So why not just test the car in the form that it would be supplied for sale?

What you refer to here as leeways, previously as loopholes, I see as fraudulent behaviour or cheating to encourage people to buy their car rather than their competitors. I have heard the suggestion that this does not matter because all the companies are cheating, but I have no sympathy whatsoever for that argument. Modifying cars prior to testing should be reported to the equivalent of Trading Standards. I do not know what extent the modifications improve the fuel economy figures but I have seen suggestions that they do make a significant difference. The reason that I want to focus on modification of cars is that there is a good chance that consumer pressure could end the practice.

Unless you can provide evidence to the contrary, I will continue to believe that it is the manufacturers that are delaying the introduction of WLTP testing. There is considerable evidence that this is the case.


Hi both, we’re just trying to bring the subject to life and using other scenarios to help others visualise the problem. We’ve covered this subject a lot of times, and since Convo is a more informal place we wanted to put a new spin on it. I’m sure you can think of some better comparisons though 🙂


wavechange, I have no expertise in car emissions or mpg, nor any axe to grind in favour of the industry, so rely upon what seem to be authoritative and independent reports – some I referenced earlier. None I have found have practical results for the effect of taking advantage of the leeways given in the NEDC test regime. However, from calculating the possible effects it seems unlikely that any more than 1/3 of any improvement in emissions (not total emissions, just improvement) is down to the leeway, and probably less, the majority being due to technical improvements. So I can only base my comments upon what seems to be evidence rather than conjecture.However if someone can point to other fact-based information I’d be interested to see it.

As far as introducing the WLTP test I would like to see it invoked as soon as possible – but it will still not give real life data, just be a bit closer, so we’ll still need Which? and Honest John etc reporting what they test and what drivers report to get an idea of what we will be more likely to achieve in practice. Does anyone actually know (rather than believe) why the test is being delayed? Perhaps Which? could ask both the EU and the ACEA (who represent the European manufacturers) for the reasons. Then we might have a better understanding.


wavechange, “The reason that I want to focus on modification of cars is that there is a good chance that consumer pressure could end the practice.”. I want this also – all cars should be tested under as near the same conditions as is possible in a laboratory / test house situation and as near the standard vehicle offered for sale as possible. I believe that the new test proposals tighten up the test procedure.

I found some news on the attached link http://www.airqualitynews.com/2015/05/20/eu-adopts-real-world-vehicle-emissions-testing-procedure/. I don’t know their status.

EU information can be found at http://ec.europa.eu/clima/policies/transport/vehicles/cars/index_en.htm


If you are serious about lightening the mood on this topic why not log onto YouTube – Auto Expert.com.au – John Cadogan – Is My Car’s Fuel Consumption Too High?


John Cadogan seems to talk a lot of common sense Beryl.


Doesn’t anyone think it ironic that “real mpg” is a cause celebre worthy of many articles but duff washing machine temperatures are of no interest?

Given I know I can alter my MPG by around 20% easily by driving style or routes chosen it seems a minor concern to dwell on the subject. There are several motoring magazines and on-line sites all discussing this sort of thing and even providing real-life data. If car purchasers wilfully choose not to investigate a major buying decision fully then so be it.

However knowing whether a washing machine can deliver a wash at 60C is not something the average consumer can find out about. Now call me simple but surely a consumer body should highlight details such as this in its super-slick listing.


dieseltaylor, perhaps you could come up with a headline to inflame public opinion about this? It seems the way to do it.


Perhaps we should discuss this in a Conversation about washing machines. This is Nic’s first Conversation and it be good to keep it on topic.


dieseltaylor makes a valid point that relates to the topic.


wavechange –

I am not saying anyhting is wrondg with Nic’s piece. In fact he is agreeing with me that consumers need honest and useful information not some bogus industry arrangement with the EU. The EU is behind the duff mpg test AND also the concept that 60C wash means whatever a manufacturer wants it to be.

Which one might impact your health ?
Scientifically speaking is it advisable to let people know that 60c is not a real figure?
Should washing machines able to perform the NHS wash cycle recommendation be noted?

Bottom line is can a consumer association hold two different views on the sanctity of, or otherwise, of misleading data being peddled to the public.?


Dieseltaylor – I’m more than happy to debate the points you raise as long as we do it in one of the washing machine Conversations, and when I get back from holiday. 🙂 I’m not happy about the labelling of washing machines.


Good idea but lets have it on the new community forum as it seems it will be more searchable in due course.

I have posted nine resolutions under the Governance section which were sent to Council for consideration at the end of June. As it stands currently you need 5% of all members to ask for a Resolution to be put – and they get to pay the costs. So as you see there are some problems with the current articles and some other matters.

I hope you have a grand holiday.


I have just checked out Skoda UK’s website and it says:

“Standard EU Test figures for comparative purposes and may not reflect real driving results.”

Their official test results give a combined figure of 57.7 mpg for the Octavia 1.2 TSI. The hired one I had a couple of weeks ago did not quite manage that, but did do well over 50 mpg – a good performance for a family sized petrol car.

If the EU test does not reflect real driving conditions, then I think the blame lies with the EU and not the car manufacturers. In a competitive marketplace, it is not really surprising that manufacturers will try to maximize their scores under the EU test.


I’m now a little confused by this topic particularly about Ron’s Qashquai. Ron is claiming in an urban cycle 28.8 mpg against a “claimed” – actually the EU NEDC test cycle result – 42.8 mpg, so 67%.

If I have read Which?’s test data correctly (running costs and depreciation) for this 1.2 2014 petrol Qashquai, they quote a claimed urban mpg of 40.9, and a measured (by Which?) of 41.5 – slightly better than claimed! What matters to most people I expect is the combined result, 50.4 claimed, 44.1 mpg measured by Which?, so 87% of the claim.

Clearly, in view of Which?’s remarks in the introduction, I must have read the results incorrectly. Please put me right.

Incidentally, Nissan in their adverts say that their quoted mpg are “obtained from laboratory testing…and may not reflect real driving results”. In Which?’s overview of the car where they give mpg they are under “official manufacturer data” with no such disclaimer. It would be useful if they pointed out they are lab results that may not be reflected in real life driving.


Good point malcolm. Which? does not make the distinction regarding EU mandated figures,, but simply calls them manufacturers figures. True but actually misleading.

I see for the real world figures that Honest John’s people supply for this car the average for some people ranges from 34 to 46 mpg which rather suggests that a 33% increase is theoretically available for the worst performing. So all they need to do is change their route, their style of driving, terrain, or the time they drive at to achieve better figures.


Looking at this topic from an uninitiated point of view, I can see both sides of the debate.
For example, claims regarding washing machines are an entirely different issue when dealing with the many vagaries related to fuel consumption and given the number of ways and methods that can influence mpg already described in this Convo, I fail to understand how vehicle manufacturers can accurately come up with an entirely correct figure when advertising fuel mpg consumption.

The American Environmental Protection Agency (EPA) have more or less acknowledged this as the focus there has now switched to the connection between fuel consumption and emissions as Malcolm has already touched on above and the emphasis has recently switched to putting more pressure on auto manufactures to produce more hybrid and electric cars. http://www.fueleconomy.gov – How Hybrids Work.

It doesn’t help a topic to constantly berate the authors of a particular issue as seems to be occurring more frequently of late. More positive and innovative ideas and constructive feedback would be more welcome and be more instrumental in reaching a reasonable and fair solution to any debate.


Beryl – Possibly we have the same subjects re-shod and paraded again whilst ignoring other important matters.

The European Consumer body, of which Which? is a member, sees problem for consumers with TTIP a matter much ignored here. This blog they have started outlines where consumers may well be affected:

You will appreciate that BEUC is the useful source of data on mpg test fiddling and what is happening in other Europrean countries. Of the two campaigns TTIP is far more long term and affects all rather than a delay of a year or so with new testing guidelines for cars.


Perhaps Which? should encourage our mildy-euro-sceptic government to instigate a UK national test and to ban the use of these misleading EU test results from UK advertising? Is it not the case that our ASA can already ban misleading adverts, especially if consumers complain about them?

Furthermore, to help reduce the UK unemployment figures, perhaps the new UK test could feature Mr Carkson and/or Mr Stig taking each car for several laps around their “reasonably priced car” test circuit, using their established “Top Gear” style of driving.

I think we would then end up with a series of test figures that would be useful for inter model comparisons. But also, those of us who have to pay for our own petrol, tyres and brakes would have a good chance of exceeding these test figures in everyday use.

The test process might even be self-financing, if suitable TV companies were allowed to bid for the viewing rights.


nic, any comments on Which?”s Qashqai fuel consumption results?


Afternoon everyone, and thank you for your comments. I’ll try to address as many points as I can, but apologies in advance if I miss any out.
Firstly, to summarise, the current test is flawed and years out of date – it was never designed to accommodate modern hybrid powertrains, stop-start systems and so forth, and doesn’t include a motorway cycle – when, if you’re travelling at a normal motorway speed, an engine is working hardest because the car is experiencing the most aerodynamic drag, and so typically uses the most fuel. The extra-urban part of the current official test only lasts 6 minutes 40 seconds, at an average speed 39 mph – little more than half a normal motorway speed.
There’s also no requirement to have ancillaries – lights, aircon etc – switched on, all of which use energy and therefore fuel, and which most people will typically use at least some of the time. Accelerations are very gradual, too – far slower than you’d normally execute on an even mildly busy road – and manufacturers are allowed to switch their cars into ‘eco’ modes, which usually neuter performance to such an extent that they are almost unusable in normal driving.
And then there is the suspicion – although unproven by us, at least – that manufacturers modify their cars to lighten them, make them more aerodynamic or decrease rolling resistance. I understand they are also free to test their cars wherever they like, at whichever commercial test lab they prefer, which gives rise to the possibility that they might choose a lab that gives more favourable results, either due to its methodologies or environment. And lastly, the testing process isn’t (as far as we are aware) policed in any meaningful way – there are criteria that the manufacturers are supposed to follow, but that’s about it.
So, none of the above helps consumers get mpg figures that are close to what they will actually experience. Of course individual driving style and environment will influence fuel consumption to a high degree, but there are a great number of ways the test could – and should – be improved to make it more accurate, reliable and comparable. At least then we’d have a set of official figures we had slightly more faith in, and that were more achievable in normal conditions. The manufacturers could be a lot more transparent in their adverts about where the existing figures come from, too.
To the other points:
Firstly, the TV analogy was just there to introduce the article – I’m sorry some of you found it frivolous or irrelevant, but I was simply trying to draw a parallel with another product type and industry that people new to this topic might be able to relate to.
Next, several – but not necessarily all – car manufacturers are, we believe, trying to delay the new test by exerting influence via the European Automobile Manufacturers’ Association (ACEA). The reasons given in previous responses to our research and that of other European consumer associations (individually and via BEUC) is that they want more time to ensure the test is as robust and future-proof as possible. That’s admirable, but there may be another motive – a change to the test could not only mean their cars’ mpg figures get worse, it is likely to mean their emissions figures increase. If that happens, the manufacturers will find it harder, perhaps impossible, to meet current and future EU emissions targets, which could result in large fines.
On the mpg disparity between Ron Nicholl’s Qashqai and the one on our website, his is the automatic version, which supposedly achieves slightly better economy in the official test than the 1.2-litre manual model we tested. As to his driving style, I can only comment that he says he ‘drives like an old man’, which in the context of what he said to me certainly suggested he drives at a moderate pace rather than with his foot to the floor.
Lastly, on our website, we show ‘claimed/tested’ mpg figures for each tested model – this data appears on the running costs tab of each review. We could do more to make it clear the conditions the claimed figures are achieved under, so I’ll look into how that may be possible.
I hope that helps clarify things a little. I’ll be following this Convo and will reply to queries when I can. Thanks again for your comments.


Thanks for your input, Nic. I would like to see Which? pushing for independent testing of fuel economy and emissions because that is the only way we can be sure that tests are carried out under standard conditions.


Thanks Nic. I’m glad you highlight the severe deficiencies in the EU NEDC test that manufacturers have to use – we need to exert pressure on the EU to get the new test both acceptable and in use. I believe data from it will not be used until 2020?

This conversation is fuelled by a lot of “mights” and “maybes” and “suspicions”:
“And then there is the suspicion – although unproven by us, at least – that manufacturers modify their cars”,
“might choose a lab that gives more favourable results”
“there may be another motive – a change to the test could not only mean their cars’ mpg figures get worse,”
I think it a pity Which? does not have firmer grounds for making these comments. I also think it is a shame that Which? does not at least put numbers do these possibilities so their effect can be better appreciated,

Regarding the Qashquai your own urban figures show it to perform better than the EU test – good result? The intro says: “The Qashqai also failed to live up to its mpg claims in our test”; this seems an inaccurate comment. Ron’s example perhaps better illustrates just how individual driving habits and conditions will give a large spread to “real life mpg”. One example certainly should not be used to condemn the Qashquia.

You say regarding the delay in the test “If that happens, the manufacturers will find it harder, perhaps impossible, to meet current and future EU emissions targets” What is the point in setting targets that are not achievable? As I suggested above, why not ask ACEA and the EU why the test is being delayed.

I appreciate that to spark off a conversation an introduction with some contentious comments is helpful. However I believe those comments should be based on fact and tempered with a balanced argument, on something as important to many people as this. Otherwise it is misleading.

A positive approach would be for Which? to publicise sites where “real life” mpg can be found. Whatever EU test comes about will always be out of date to some degree and will never give real life results;real life will be a spread of data reflecting different driving styles, terrain, load and so on.


A thoughtful and useful piece Nic.

I think there is some sense in waiting for technologies to settle down and also unifying a world standard. As long as it is highly publicised that the EU mandated test is totally flawed for practical purposes then what is the problem?

Arguably it is a disservice to have these figures quoted at all and it would be most sensible to just quote the pollutant level. Then auto companies will have to quote their own figures and be lambasted and even sued if these are deceitful. Plenty of fodder for testing organisations and the auto mags.

As for Ron’s driving styles the most important variable surely is the amount of stopping and starting you engage in. Taking a car from rest to 30 mph must surely be the most fuel inefficient stage ignoring idling time so anyone who has a high number of stop starts and queuing for junctions is really going to suffer different figures.

A little research brings us to this on Wikipedia which is helpful in explaining where losses occur. https://en.wikipedia.org/wiki/Energy-efficient_driving


Hi Malcolm, the 1.2-litre petrol (manual) Qashqai we tested slightly bettered its urban mpg figure, but it fell far short in the extra-urban part of the test, and the overall combined mpg figure was as a result much worse than claimed. The diesel model fell far short of its claims across both the urban and extra-urban cycles.
As I’m sure you can appreciate, until we have concrete proof of wrongdoing – first-hand evidence of tests being manipulated, for example – we have to remain cautious in how we describe these matters. It is an ongoing body of work.
The EC will make a decision this autumn about whether to implement the new tests as planned or to delay it – until then, it isn’t being delayed, factions are simply lobbying for one result or another.
More accurate mpg figures for more than 1000 cars are available on which.co.uk. These include measurements taken from a motorway cycle, and we test with aircon, lights etc switched on.


nic, if I read the Which? test figures correctly, achieved results of the Qashquai compared with EU tests were: Urban 41.5mpg = 101% of EU 40.9 mpg; Extra urban 48.7mpg = 84% of EU 57.9. Combined 44.1mpg = 87.5% of EU 50.4.

Considering how out-of-date and unrealistic the NEDC test is, I could not describe these figures as “falling far short” in any critical way. They are simply illustrative of the EU test deficiency. A “real life” figure for the Qashquai from one source gives an average mpg as reported by owners of 39.mpg. I think this shows that standardised tests will allow comparisons between cars but if you want a “real life” figure you need to look at what owners achieve in practice.

“until we have concrete proof of wrongdoing “. I would like to see, as I’m sure would everyone, proof of what is actually going on. Are manufacturers presenting results obtained fraudulently? Are test labs producing false results? But just suggesting, as Which? does, that there “may be” wrongdoing, given its status, carries weight with readers. So it would be very helpful if you gave us the reasons, and evidence however limited, that Which? has to make the claims suggested in the introduction.


Hi Malcolm, I mentioned the Qashqai in this Convo because Ron got in touch about his experiences – it’s a single example from many, many of which were covered in the article published in the May issue of Which? magazine.
There are different ways you can look at the figures – the difference between the claimed and tested extra-urban mpg is 9.2mpg. That equates to nearly 16% of the claimed mpg figure, which is a significant difference in my view.
In terms of proof, here’s one example: the Italian consumer association replicated the official tests and achieved much poorer mpg than two manufacturers did, which was sufficient evidence to launch a legal case:


nic, thanks for your reply. The significant difference is still largely down to the out of date EU test, isn’t it?

I have looked at the BEUC document before. It rightly points to the deficiencies in the NEDC test cycle, and its “loopholes” – which some would argue are looseness of the test protocol that manufacturers can take advantage of. That does not mean using them is fraudulent – it means the EU should have tightened up the test regime.

The claims made legally against two manufacturers are quite different. The implication is that these manufacturers have produced fraudulent results. If this is proven then I will be the first to condemn those manufacturers. If, for some reason, the differences are down to the way the tests can be conducted, then its back to condemning the EU test. I’ll be interested to see the outcome.
But one example is not proof that the whole motor industry is deliberately misleading us, is it?


No, you’re right – but we’re not insinuating the whole industry is doing that either. In this Convo we question whether the manufacturers could be doing more to highlight the official figures do not reflect real-world conditions. When Mitsubishi states 148mpg on its website alongside its Outlander PHEV (http://www.mitsubishi-cars.co.uk/outlander/explore-phev.aspx), for example, there is no mention of the specific test conditions this mpg figure was achieved under.
Manufacturers do appear to be exploiting a set of rules, just as F1 teams to, in order to gain a competitive advantage and the problem is the flawed test. Addressing that is our primary concern, but we would also like to stop consumers from being misled, intentionally or otherwise, by adverts that lack transparency or suggest the results are readily achievable.


nic, the Mitsubishi PHEV simply serves to show how useless the NEDC test cycle can be. It was devised before any thought of electric or hybrid cars so is simply not appropriate. But I assume manufacturers have no option but to use the NEDC test cycle? Even giving the usual disclaimer would not deal with the disparity – unless you are saying Mitsubishi have misused the NEDC test and are providing falsified figures.

An important figure for many may be the CO2 emissions, rather than mpg, because this affects VED and company car tax. Assuming Mitsubishi have properly tested the car the NEDC results in 44 g/km, so no VED and only 5% company benefit tax. This is clearly a nonsense result because as you show the CO2 is nearer 160. But what figures do you expect Mitsubishi to publish – indeed, what are they allowed to publish? It’s a weakness in the taxation system as well as the test that makes this unrealistic situation financially attractive. A look at any road test for “real life” figures will show mpgs ranging from 32 to 67.3 (your test figure) compared with the NEDC 148 – presumably only obtained in the short test using mainly battery power – with no regard for the CO2 created in producing the electricity used to charge the car of the mains.


The BEUC reference what I think is a well written and objective report on the discrepancy between NEDC test (so-called “manufacturers’ claims”) and “real life”. http://www.theicct.org/sites/default/files/publications/ICCT_LabToRoad_20130527.pdf

I have tried to fairly extract snippets, but well worth reading if you have an interest. My comment in (..)

The NEDC was a type approval test (i.e. usually pre-production) and was never intended as a means to derive a representative CO2 value. It was designed primarily as a reproducible test……. (hence yielding comparative results).

Manufacturers are doing nothing illegal

Real CO2 emissions in 2001 were 7% above test, in 2011 23% above. All vehicle manufacturers were similar. (probably largely down to increasing disparity between the test regime and real life driving, changes in car technology and no doubt exploiting the test regime. The report discusses this at the end)

(When CO2 emissions achieved even more importance commercially as tax bands were introduced there was an effect on test results as manufacturers strove to get cars just into lower bands – through technical changes and no doubt by using the test regime as far as possible to help)

WLTP – the new proposed test regime, initially gave mpg figures very close to the NEDC!

In USA the tests are performed on cars that must be as close to production as possible. Their CO2 discrepancy was 32% from real life.

So this is a very mixed picture. A very poor test when being used for something it was not designed for. Car technology has far outpaced the test. Nothing illegal going on, but no doubt to maintain competitiveness manufacturers will seek, within the test protocol, to get the best outcome (who would not?).

The answer is a better more rigid test allied to publicity of where to find “real life” mpg. In support of the latter I understand the USA uses “multipliers” derived from real-life reported data to convert test results to something more meaningful to the motorist.



Actually altogether probably over $0.5Bn. Nice to see large boots being aimed at offenders.


What is good about this (or bad if you like) is that it seems a manufacturer who has been cheating on the figures has been fined – because that fine will not necessarily be passed on to consumers – just don’t buy their cars if you don’t want to help them pay it.

What I wonder about, though, is the EPA’s requirement that in future manufacturers must test on the road, not the lab. I cannot see how this can give consistent results due to, for example, road topography and surface, variation in driving style, climate and so on. The NEDC rolling to stop test on a road surface is known to be problematic. It will be interesting to see how they frame their test procedure.


A Vauxhall ad in the DT today is an example of how not to present performance data. It is headed “Official Government Test Environmental Data” in letters 4.5mm high. Only when you read the small print a third the size doers it tell you that actual performance will depend upon driving style etc.

We should have approved standard wording and be clear it does not depend upon driving style at all – the figures given are largely irrelevant because the EU test is substantially useless.


I think it would be better if we didn’t have any figures published by manufacturers but could access a table drawn up by an accredited independent testing house.


Although Which? is pushing for the new tests to be introduced by 2017 rather than delayed to accede to the demands of some manufacturers, I have not seen Which? pushing for independent testing. I am surprised because Which? has promoted its own independent testing for many years.

Having trustworthy test data available online would be a great help for anyone in the market for a new car.


Real life figures are the most useful to motorists – see a number of websites. Test data can be used for emissions to set tax bands.
Which manufacturers are demanding the tests be delayed?


There are numerous references to members of ACEA seeking to delay the introduction of WLTP testing until 2020. This one mentions the possibility of an extra year being needed: uk.reuters.com/article/2015/05/06/eu-autos-idUKL5N0XX3U020150506


I read this Reuter’s snippet when it came out. It does nothing to explain the situation, just speculates. The question is about emissions rather than mpg as these are the limits set by the EU. What needs to be explained is whether the proposed standard will be sensible, yield good comparative results and whether carmakers can meet the deadlines proposed. I suggest we ask the EU for their assessment.


This letter to the EU http://www.acea.be/uploads/press_releases_files/Open_Letter_to_European_Policy_Makers.pdf
“Pointing out that political measures restricting the rollout of the new generation of diesel technology would undermine existing efforts to cut CO2 emissions, the associations called on policy makers to help accelerate fleet renewal and the introduction of the cleanest vehicles.”
This suggests there is perhaps more to this than rhetoric suggests.


Which? News today says:
“EU law requires carmakers to show official test figures in their adverts to help consumers compare fuel economy between different models. But we think the figures should also reflect real-world driving – and if a brand quotes an mpg figure in its adverts, a consumer should be able to achieve it in normal use.”
I agree that “real life” mpgs are the only ones of use to drivers. However just how would you a) derive that figure for new models, b) where would the “real life”figures come from so they were consistent model to model and c) how would you phrase the advert so a motorist not achieving the mpg would not be able to claim misrepresentation (perish the thought!).

“Real life” mpg will not be a single figure but a spread – probably wide – depending upon journey type, driving style, and a lot of other factors – “normal use” will be an average with as many getting mpgs below as will above. It’s a nice thought but I cannot see it being practical. What I would support is a responsible independent organisation collecting “real life” mpg from all the major groups that publish them and having the car manufacturers literature and adverts refer potential purchasers to them.

Even the proposed new test will not give “real life” mpg.

RogerC says:
3 August 2015

My main concern is that my car’s “computer” states that I am getting about 5mpg more than my calculations. I always fill my tank each time then calculate real mpg from miles (usually around 450) from the last fill and fuel added . I reset “computer” after each fill.
When I hear others stating how good their mpg figures are it usually turns out they are relying on their car’s “computer”.
Is this another way for manufacturers to disguise the differences between quoted and actual results ?

ferkemall says:
3 September 2015

Ah fuel economy testing, well its all done a wind tunnel lab they take out the seats spare tyre,and anything they can to lighten it up then they gaff tape the gaps and off they go ,the result is it does a 100 mpg ,of course when you buy it and get the kids in and the wife /shopping you end up with 31 mpg !


In 2013 I purchased a Vauxhall Corsa which was deemed to produce around 56 mpg but which, in fact, did 22 mpg (rural)! I had the engine checked twice without any fault showing. A year later I part-exchanged it for a Toyota Yaris hybrid which could produce between 55-82 mpg depending on which type of road it was driven, town driving being the most economical. Living in a rural area I get between 45-55 mpg but relative to the Corsa this is a saving in petrol of over £100 monthly! My dislike of the Yaris is that it is too small and uncomfortable so I am again considering the purchase of another car. There are a number of larger equally economical cars on the market but currently my attention is drawn towards the Skoda Greenline 1.6. I find Honest John’s site useful for what users know of the fuel consumption of their own vehicles. The following video is about the Australian car industry which is both interesting and amusing and probably factual: https://www.youtube.com/watch?v=hTfAEh27lQM. On calculating the cost of running a car this time I am going for a private contract hire which seems the cheapest method.