Misleading MPG figures from MB?

[lolboy147]

Am I the only one who feels that MB should be taken to task for the MPG figures they quote?

I have now put around 3000 miles on my new E350 Coupe CDI. The MB quoted MPG is 38.7 Urban, 47.1 Combined, 57.6 Extra Urban.

I am currently averaging 34.9, and given that most of my driving is cruising on a motorway I struggle to comprehend how these number could ever be achieved. I have driven the car at a steady 65mph on the motorway and still not got 40mpg. How on earth would you ever hit the numbers they quote.

I have read other posts talking about how the engines are tight (fair enough) from new but I don't want to wait 5 years until my engine loosens up and starts giving improved mpg.

Do we have any recourse with MB? I bought my car having read how economical it was meant to be. Now did I ever really expect to hit those numbers - not really - but I'm not even achieving the urban number for my 80% motorway driving. How can that be acceptable?

I'll be very interested to see other peoples views and experiences here, as I am inclined to take this complaint up officially with Mercedes.

 

[Alex M Grieve]

Am I the only one who feels that MB should be taken to task for the MPG figures they quote?

I have now put around 3000 miles on my new E350 Coupe CDI. The MB quoted MPG is 38.7 Urban, 47.1 Combined, 57.6 Extra Urban.

I am currently averaging 34.9, and given that most of my driving is cruising on a motorway I struggle to comprehend how these number could ever be achieved. I have driven the car at a steady 65mph on the motorway and still not got 40mpg. How on earth would you ever hit the numbers they quote.

I have read other posts talking about how the engines are tight (fair enough) from new but I don't want to wait 5 years until my engine loosens up and starts giving improved mpg.

Do we have any recourse with MB? I bought my car having read how economical it was meant to be. Now did I ever really expect to hit those numbers - not really - but I'm not even achieving the urban number for my 80% motorway driving. How can that be acceptable?

I'll be very interested to see other peoples views and experiences here, as I am inclined to take this complaint up officially with Mercedes.

I wonder if this is an issue which has been highlighted by the more ambitious claims made for the newer generation efficient cars?

I have always managed to beat the "combined" figure taken as an average throughout my ownership of the older generation cars. On the other hand, even with careful driving I have rarely hit the "extra urban" figure.

I believe the numbers are derived from theoretical calculations rather than any "brim to brim" results obtained in the development and trials phases of new models.

Perhaps the formula they use is flawed, but it is almost certainly defined by higher authority for use by all manufacturers.

 

[lolboy147]

I think you're correct re the "theoretical" calculations. However, MB, and other manufacturers don't make this clear at all. I have to consider that this is not by accident but by design in their marketing literature.

My last car was a 2006 Jaguar S type - 3ltr petrol engine. That delivered more or less exactly what Jaguar quoted for my combined mileage. This led me to believe, naiively it turns out, that I might see similar accuracy, or proximity to the MB claimed mpg figures from my new MB. More fool me I guess.

But should manufacturers be allowed to quote these figures? At best they are misleading. I could use other words but I'm mindful that there could be legal implications.

 

[st4]

The test IIRC has not changed, and before cars gave a return that the owner would usually get within 10% of worst case.

Here, new cars do the same laboritory condition test, and return way better MPG on that test, yet are worse than older models for owners.

I suspect engine mapping is now so specifically designed for that lab test that out in the real world, the electronic parameters for the engine are not in touch with reality at all.

 

[Rory]

I believe the numbers are derived from theoretical calculations rather than any "brim to brim" results obtained in the development and trials phases of new models.

They run an internationally approved test over a very short distance - http://www.direct.gov.uk/en/Motorin...atethefuelconsumptionCO2andtaxcosts/DG_195297

It's obvious that cars will be engineered to do well at the test and that affects the emissions ratings and therefore has an impact on company car tax and road fund duty.

The test is going to change to be more "real world" but it's looking like it'll be 2020 before it comes in.

MB did get sued by an owner in Germany for poor fuel consumption (and it was only 9% out) and they had to pay compensation. In the US there are constant legal battles against various manufacturers for poor actual MPG.

 

[daveyjp]

Honestjohn reported average mpg from owners is 36.8mpg. Lowest 32, highest 39 so your figure is in line with other owners.

 

[television]

I did 148 miles today ½ m and ½ A &B roads and returned 28.9 beating the claimed figure with ease. OK I did not accelerate much and just went with the flow

 

[Alex M Grieve]

I did 148 miles today ½ m and ½ A &B roads and returned 28.9 beating the claimed figure with ease. OK I did not accelerate much and just went with the flow

did you beat the combined figure, or the extra urban figure Malcolm? (excellent mpg for your car in either case).

 

[television]

did you beat the combined figure, or the extra urban figure Malcolm? (excellent mpg for your car in either case).

The extra urban Alex is around 30-31mpg I can get to the 30 on many journeys, I will wait till I go to Sweden to beat it It is a huge beast

 

[st4]

I've beaten extra urban, 47mpg on my car, seen 52mpg from it.

Was a chore to get it to 52mpg but 44mpg is real easy and mine combined sits at 37mpg.

I drive less these days, so rag it a bit more and 35mpg seems an acceptable MPG when driving quite fast in a large powerful automatic car.

Given the same engine powers new blue effencieny cars give take some engine mapping and injectors plus a DPF, I don't see where merc have plucked out such high MPG numbers from the OM642.

 

[television]

I am looking forward to getting a 2011 CL with the blue engine, it has near on AMG performance plus much better MPG.

Its a few years off though yet, the premium bonds payout is to mean right now

 

[Seeker_UK]

Extra urban in my E320CDI is supposed to be 50+, I've never seen 45. :-(

 

[television]

Extra urban in my E320CDI is supposed to be 50+, I've never seen 45. :-(

You are not trying hard enough

 

[Seeker_UK]

You are not trying hard enough

So it would seem.

What's the trick then? Buy an E220?

 

[whitenemesis]

Cars are tested to industry-wide standards and are meant for comparison between models and manufacturers. They are, at best, just indicative of what could be achieved in the real world. To replicate laboratory conditions would be impossible on your daily commute!

 

[television]

So it would seem.

What's the trick then? Buy an E220?

Accelerate just fast enough to get it in top gear as soon as possible, keep to about 45mph, take your foot off the throttle way before when the lights are red.

Slip streaming a lorry is very good

 

[Seeker_UK]

I am being a bit tongue in cheek.

My last car, a Saab 9-3 1.9TDI averaged 38mpg for me.

The E320 averages 33 which for 2 extra cylinders and a bit more refinement is pretty good.

 

[whitenemesis]

Accelerate just fast enough to get it in top gear as soon as possible, keep to about 45mph, take your foot off the throttle way before when the lights are red.

Slip streaming a lorry is very good

Can play havoc with the paintwork though...

 

[television]

I am being a bit tongue in cheek.

My last car, a Saab 9-3 1.9TDI averaged 38mpg for me.

The E320 averages 33 which for 2 extra cylinders and a bit more refinement is pretty good.

The petrol Saab's were very good too, I had the 9-5 diesel for a week, that thing did shift

 

[Mic]

Over the last 1110 miles my C140 has averaged 21.1 mpg and over the last 920 miles my R230 has averaged 19.5 mpg

Mic