The test is most certainly flawed but if it told the truth we would all be paying £100's more in road tax every year and company car users £1000's more in company car tax.

All it needs is for buyers to be realistic about mpg and remember the savings you are making in tax. Our 2 litre diesel BMW has 143bhp and a combined of 62.8mpg, never in a million years. It does 48 mpg on average which I am delighted with, the 130 bhp Mondeo we had did about 40 mpg in the same circumstances.

88mpg in a Kia Rio, never while there is a "y" in the day of the week.

those mpg are the same for my merc C220 coupe (143 bhp), the best i had was 66mpg over a 200 mile run (had to try really hard to get that!!) the overall for 25,000 miles is 48 mpg.. much better car than a bmw btw :-)

THe test is a standard test for all cars. It is used to compare like with like. It is not meant to demonstrate how it will perform on normal roads for normal use. Crazy idea but as I said all cars have to do it and it is done the same way for each/every car which would be impossible on the road.

but my B-I-L can't get anywhere near the quoted figures for his Start-Stop Yaris......

Not surprising, isn't 40% of the urban test stationary? Stop start would score very well there but unless you live in London the chances are you're moving and your engine is running so you won't meet those figures.

Even my car is economical when it's not going anywhere.

Manufacturers fuel economy figures should be taken with a large dose of salt.

They're not manufacturers figures though, at least not like the over-optimistic advertising claims that used to be made.

These are figures based on a standardised test that has to be complied with by the manufacturer. If the EU bureaucrats carried out the testing themselves to avoid claims of exaggeration, the results would be the same.

The problem is that the test standard just isn't reflective of real life driving - it's the test standard that needs changing.

Edited by RT on 20/07/2012 at 22:31

But some of those figures are pure fantasy depends where you live how you drive and what sort of driving you do.All thatmatters is what it costs you personnally not other peoples costs.

But a single average, however accurate, isn't helpful to an individual person with a unique usage pattern - because cars don't have the same relationship between urban commuting and long-distance cruising as each other.

If an individual owner does predominantly long-distance cruising then the comparison between cars needs to be on that basis as differences in urban consumption have little significance - and vice versa.

Go back to the late '70s and use the Urban and 75mph tests from those days.

Your right these parts have been used in petrol engines for years its just that HJ has not noticed.

And DPFs are more likely to be a problem when diesel was the wrong choice in terms of usage pattern and annual mileage.

All modern engines, petrol or diesel, have some horrendously expensive componentry which might go wrong but don't often.

For petrol engines to compete with diesels on consumption, more are using highly stressed direct injection turbo which will mean even more potential expense.