Claimed fuel consumption not true according to survey (ICCT)

[Zafiro]

Cars in Europe use more fuel than it says on a paper according to a survey from International Council on Clean Transportation. Average the car use 25% more than the car maker claim. 10 years ago the difference used to be 10%. All the data is based on half million people and their cars.

According to ICCT:

Worst:
BMW: +30
Audi: +28%
Mercedes: +26%

Best:
Peugeot: -16%
Citroen: -16%
Toyota: -15%

EU is working on new rules coming in year 2017.

Source: http://www.theicct.org/laboratory-road
http://www.teknikensvarld.se/2013/05/28/40601/bilarna-allt-samre-pa-att-halla-utlovad-forbrukning/

 

[ACE]

It is possible to achieve manufacturers fuel consumption claims... on a downhill, with a tailwind and changing gears at 1500rpm

 

[EnI]

I guess it all boils down to the driving style? I guess BMW, AUDI & MB drivers don't really drive in a way to save some gas, don't they? While I can see Toyota, Peugeot, Citroen, Renault, Fiat & Ford etc driver to be more careful not to have too heavy foot & more conscious about fuel consumption etc.

And manufacturer's claims are based on predicted average driving style & conditions, so ...

It's not a surprise that sporty & luxury brands / manufacturers are the biggest "cheaters" ...

Take eg. the same VAG engine & transmission, featured in different VAG model (Skoda, Seat, VW, Audi) - which mostly have a similar weight & similar claimed fuel consumption figures, yet I bet the bigger discrepancy between claimed & real fuel consumption figure would be @ Audi & Seat, and less @ VW & Skoda.

 

[martinbo]

I guess it all boils down to the driving style?

Yes, absolutely - but not the driving style of the cars' owners. It's the driving style of certified, professional test engineers - with laptops plugged into console ports with all kinds of telemetry information at their disposal - driving on absolutely flat roads well outside of peak hour traffic cycles with all power-draining accessories switched off. These figures are the biggest consumer con in the car industry and cannot be replicated by regular customers in real-world driving scenarios.

 

[Betty Swollocks]

I think the test cycle is conducted in a laboratory so has absolutely nothing to do with real world conditions.

I myself keep a record of the fuel consumption data on all the cars I own or drive for a few days at a time. I'm going to create a thread soon with the info. I conduct the tests in an extremely accurate way.

My latest data is on the F10 BMW 520d. I achieved 51.2 mpg over 1,949.1km last weekend.

 

[martinbo]

^ I'm looking most forward to that thread Betty.

 

[Betty Swollocks]

^ I'm looking most forward to that thread Betty.

Thanks. I've got all the data gathered and just need to decide how best to present it and in which forum.

 

[Giannis]

Thanks. I've got all the data gathered and just need to decide how best to present it and in which forum.

Make a few MS Excel tables, export them to pdf and make a library of your data under the showcase feature: http://www.germancarforum.com/community/showcase/

That way you will be able to have all your data gathered in one place, you'll be able to update them, plus you could also upload photos, write a small summary and most importantly, this showcase item will create a discussion thread automatically linked with everything I mentioned in this sentence.

You could try it out first and if you are happy continue with it, or if you're not, start a thread under the "Tech talk" forum.

 

[Betty Swollocks]

Deleted.

 

[ACE]

I myself keep a record of the fuel consumption data on all the cars I own or drive for a few days at a time. I'm going to create a thread soon with the info. I conduct the tests in an extremely accurate way.

Sounds good. I would also appreciate it if you could explain how you ensure "extreme accuracy" when you post the data. Thanks in advance.

 

[Betty Swollocks]

Sounds good. I would also appreciate it if you could explain how you ensure "extreme accuracy" when you post the data. Thanks in advance.

I'll tell you now. In order to ensure the data is as accurate as possible, and in order to be able to compare the data, I always check the tyre pressures to ensure they're at their optimum (always using a digital tyre pressure gauge), I don't drive with the windows down (improves fuel economy), I drive in the same manner with all the cars (cruising at 120km/h). If any of the vehicles have a more efficient programme available such as "ECO PRO" on BMW's, then I will use it. When brimming the tanks I always make sure they're just that. Sometimes certain cars have their own little quirks and the tank appears full when in fact it isn't. I've learnt these quirks over the years. Any changes in the above means I will either not use the data or I will mention it when I post the results. This could be periods driving more aggressively than normal or unusual things such as strong headwinds. I always use standard fuel. Either standard diesel, 95 unleaded or 98 unleaded in high performance vehicles.

In a nutshell, the results which I post will be, in my opinion, very accurate and completely typical of the fuel economy anybody could expect when driving these cars.

 

[kip]

Not to spoil your fun, but actually I think in the report Peugeot and Toyota only lie 15-16%. Its still +15-16%, not -. Figure 8 in report. Correct me if Im wrong, its just journalists not understanding a word they read.

http://www.theicct.org/sites/default/files/publications/ICCT_LabToRoad_20130527.pdf

 

[LaArtist]

It is known that BMW always over estimate their figures

 

[Betty Swollocks]

It is known that BMW always over estimate their figures

Actually, from my experience BMW are one of the better manufacturers at providing accurate fuel economy figures.

 

[Zafiro]

My experience with BMW after 10 years is that the diesel versions are more accurate than gasoline cars. Anyway, BMW, Audi and Mercedes are the worst liars according to this survey.

 

[LaArtist]

Actually, from my experience BMW are one of the better manufacturers at providing accurate fuel economy figures.

I was talking about all numbers.. performance and economy..

PS
My BMW drinks waaay more than it should.. i want to throw it in the garbage

 

[Zafiro]

I was talking about all numbers.. performance and economy..

yes, average of 4% more than Mercedes. WoW!

 

[Sunny]

I was talking about all numbers.. performance and economy..

Ah, maybe you can you give us a few instances of BMW overstating performance? Cause in my long years of following BMW and cars in general I haven't found many cases of tests and reviews where the numbers were poorer than the factory claimed numbers.

 

[LaArtist]

yes, average of 4% more than Mercedes. WoW!

Sh

 

[LaArtist]

Ah, maybe you can you give us a few instances of BMW overstating performance? Cause in my long years of following BMW and cars in general I haven't found many cases of tests and reviews where the numbers were poorer than the factory claimed numbers.

All i know is my BMW is slower and more thirsty..

And my previous one was to..

Do i have any data to back it up..not really, other than a hurry to get somewhere and an empty wallet: