Car Fuel Consumption Data

remlapd

Fuel consumption data in the UK follows a system set out in EU Directive 93/116/EC as amended by Regulation (EC) 692/2008. The Directive describes the testing procedure which aims to provide consumers with standardised information. The system in the USA shares a lot in common with the EU approach. They both test in a laboratory using a dynamometer or "rolling road" but the test conditions and durations are different. Scanning both approaches makes me wonder if the US test gives more reliable results. For instance, they test for longer "distances" that the EU equivalent. As an example, the EU test results for a Lexus GS 450 F-Sport hybrid are ; Urban 40.9 MPG, Extra-urban 49.6 and Combined 45.6. The US test only gives results for the entire GS 450h model range but the F-Sport is the most thirsty. The US results, converted from US to UK MPG (their gallon is different from ours) are : City 37.2; Highway 40.8; Combined City/Highway 34.8. That's a big difference! The question is - which is more real-world realistic, the EU or US test? Does anyone know if there's been any detailed comparisons made?

Marktheshark

They should have to quote owners actual figures, from a pool of owners surveyed.
Funny enough where such figures exist on websites, they appear to be almost uniquely accurate to the mile.
Why have laboratory tests when actual real figures for most cars from pooled owners stats are inherently accurate.
Just put that, job done, real MPG in real cars with real owners.

remlapd

I couldn't agree more but I see the point of standardisation. If we only had feedback from drivers the manufacturers would have to wait a long time before they could publish figures in their brochures. My issue is with the test itself. Look it up - it's so limited it's hardly surprising that drivers don't always see the same results. At least the American EPA test runs for longer. Maybe that explains why their results are lower than ours (must admit I haven't compared data for other vehicles, though).

forgotmyname

One of the car consumer shows did a piece on car emissions and mpg figures, Some so caled eco models actually produced more pollution than the models they replaced.

But die to the way they test them a few tweaks can be made to enhance the figures.

Even though tolerances are much tighter these days, you can still get a car off the production line where it will produce more power and give better economy than the average across the production run.
Nothing to stop them cherry picking that car and then making further tweaks.

The show in question took a car and removed the seats and extra bits of trim to make it lighter then taped over gaps to make it more aerodynamic.
They also mentioned that some manufacturers could easily remove the drive belt also to reduce the power drag from aircon and alternators.

A vehicle should be taken from the production line with zero mods and tweaks.

weeowens

This works for my car: http://www.honestjohn.co.uk/realmpg/


It is virtually spot on.

LandyAndy

weeowens wrote: »

This works for my car: http://www.honestjohn.co.uk/realmpg/


It is virtually spot on.

It's reasonably accurate for my Mazdas but hopelessly wrong for my son's Peugeot 307.


Official 38. Real 33. Son's car consistently does 40-41.

Indout96

weeowens wrote: »

This works for my car: http://www.honestjohn.co.uk/realmpg/
It is virtually spot on.

Not got my car on 2015 Focus ST Diesel but o my old car (2014 Focus ST Petrol) the only way you could get the 30 mpg average it claims would be 90% motorway cruising my journey is built up 35% open duel carriageway for the rest and I was getting 24 mpg average (the ST Diesel gets 44 average)

bod1467

That site overestimates for my Golf GT 2.0TDi Bluemotion. (I get about 51.3 ... the site suggests about 56.8).

insert_random_name_here

Get real world consumption figures (and track your own) at fuelly.com