Misleading MPG figures from MB?

[gizze]

After 1.3 miles my CL500 was up to 80c this morning and the car was out all night , it was doing 22.9 mpg at that point in time

Positively frugal!!

Seriously though, my E350cdi would often show 23mpg doing the 6 miles to my sons school on the morning, and would be at around 50-60ºc depending on the time of year.

 

[e350cdi]

I have just purchased the new e350 BlueTEC and after 4500 miles (90% of which are motorway) I'm only getting 30.2mpg at best.

The published figures are:

Urban 40.4
Extra-urban 57.7
Combined 49.6

On the basis of the Urban MPG I am at least 25% down on my expected consumption.

I have put the car into my dealer today to have it looked at today but unless they come up with something fast, I certainly plan to take Mercedes Benz to task on their misleading figures.

 

[television]

I have just purchased the new e350 BlueTEC and after 4500 miles (90% of which are motorway) I'm only getting 30.2mpg at best.

The published figures are:

Urban 40.4
Extra-urban 57.7
Combined 49.6

On the basis of the Urban MPG I am at least 25% down on my expected consumption.

I have put the car into my dealer today to have it looked at today but unless they come up with something fast, I certainly plan to take Mercedes Benz to task on their misleading figures.

I get 29.9 MPG from my CL500 on a run.

 

[Neil H]

I have just purchased the new e350 BlueTEC and after 4500 miles (90% of which are motorway) I'm only getting 30.2mpg at best.

The published figures are:

Urban 40.4
Extra-urban 57.7
Combined 49.6

On the basis of the Urban MPG I am at least 25% down on my expected consumption.

I have put the car into my dealer today to have it looked at today but unless they come up with something fast, I certainly plan to take Mercedes Benz to task on their misleading figures.

There is something wrong with your car. I get 38 out of my CLS which is far heavier than yours and if I try on a run, 44/45 is easily achievable. I look forward to finding out what is wrong?!

 

[Rob law]

MPG

Doing the same journey my wife will get around 44 mpg and I will get 40 mpg S Wales to Heathrow, we do roughly the same speed but I must be heavier on acceleration. However I have found MBS claims very optimistic in the past and none of my cars achieve MBS claims.

 

[Beeem]

I have just purchased the new e350 BlueTEC and after 4500 miles (90% of which are motorway) I'm only getting 30.2mpg at best.

Maybe you have the two position accelerator - on, and off?

Can you really expect to be getting optimum mpg with only 4500 miles on the clock??

 

[e350cdi]

Maybe you have the two position accelerator - on, and off?

Can you really expect to be getting optimum mpg with only 4500 miles on the clock??

I agree with your point regarding my low mileage however on the flip side I also wouldn't expect to be 25% down on the worst case scenario.

I dont accelerate heavy and I also use cruise control where possible set at between 75 & 85mph on the motorway

 

[geraldrobins]

The official tests are conducted at 20 degrees. The lower temperatures in the UK currently will adversely affect fuel consumption especially on short runs.
On my 30 mile run to work my mpg is down by 5 -10% compared with the summer months.

 

[grmc]

e350CDi - it looks like you're in the same boat as me.

Let me know how you get on with the dealer - mine took my car for a pootle with absolutely everything on the car switched off except for the ignition and managed to drive slow enough to hit 47mpg and claimed it was "normal". This was despite admitting that they would never drive a car that way normally, nor would they expect a normal person to.

My real complaint is that *other* manufacturers have published figures that their owners seem to be able to hit, or get quite close to. I work with people who drive Audi (2.0 turbo diesel), BMW (2.0 turbo diesel), Jaguar (2.2 diesel turbo) and know others who have Mercedes (ML diesel turbo, SLK diesel) who drive in all conditions, short or long journeys (my ML owning friend drives his ML in Canada in temperatures of between +35 and -20 C and hits the published Mercedes figures all year round). The other commuters all do various journeys, short and long, and all admit to driving their cars way harder than they've seen me driving this new car - I have taken them out in mine just in case my perception of the way I drive is way off the mark.

I've also owned many cars (petrol admittedly) and the figures are always close to the published figures.

The figures in the brochure are therefore an inducement to buy the goods, in the same way as the 0-60 times, power outputs and top speeds all are. You should no more accept a false claim for fuel consumption than you would accept a false claim on the vehicle coming equipped with Air Conditioning or a Radio.

Even if 100% isn't attainable, then I would suggest that the figures could be looked at as a general guide, and if one make's figures are 85-90% attainable for all other models then 60% should be seen as an error.

 

[L John]

I also use cruise control where possible set at between 75 & 85mph on the motorway

There are no official economy figures for cruising at these speeds.
The extra urban cycle test (yes, extra urban) has an average speed of 39mph.

 

[gizze]

e350CDi - it looks like you're in the same boat as me.

Let me know how you get on with the dealer - mine took my car for a pootle with absolutely everything on the car switched off except for the ignition and managed to drive slow enough to hit 47mpg and claimed it was "normal". This was despite admitting that they would never drive a car that way normally, nor would they expect a normal person to.

My real complaint is that *other* manufacturers have published figures that their owners seem to be able to hit, or get quite close to. I work with people who drive Audi (2.0 turbo diesel), BMW (2.0 turbo diesel), Jaguar (2.2 diesel turbo) and know others who have Mercedes (ML diesel turbo, SLK diesel) who drive in all conditions, short or long journeys (my ML owning friend drives his ML in Canada in temperatures of between +35 and -20 C and hits the published Mercedes figures all year round). The other commuters all do various journeys, short and long, and all admit to driving their cars way harder than they've seen me driving this new car - I have taken them out in mine just in case my perception of the way I drive is way off the mark.

I've also owned many cars (petrol admittedly) and the figures are always close to the published figures.

The figures in the brochure are therefore an inducement to buy the goods, in the same way as the 0-60 times, power outputs and top speeds all are. You should no more accept a false claim for fuel consumption than you would accept a false claim on the vehicle coming equipped with Air Conditioning or a Radio.

Even if 100% isn't attainable, then I would suggest that the figures could be looked at as a general guide, and if one make's figures are 85-90% attainable for all other models then 60% should be seen as an error.

Firstly, the cars they are driving might just be at their optimum with their driving style.

Secondly, Canada uses the US system which is City and Highway.
Far better than our Urban and Extra Urban as it is more realistic.

http://editorial.autos.msn.com/article.aspx?cp-documentid=1089144&page=2

Still only averaging 48mph but does include accelerating up to 80mph.

Hence why their figures are far more accurate.

Tests are over 43 miles, not our silly 6 miles for both!




Far easier to hit the US figures.
In fact when buying a car see what the US model says it does if available and use that.


Here is an example of the E250cdi

US model...
City fuel economy 28 mpg (33mpg euro)
Highway fuel economy 45 mpg (54mpg euro)

UK model....
Fuel Consumption
Urban (mpg)
47.9
Extra-urban (mpg)
65.7
Combined (mpg)
57.7


Both the same E250cdi auto saloon, but which customer do you think will be impressed with their consumption and which one do you think will feel cheated?

You can't blame the manufacturer, you can only blame the testing and yourself.

 

[Beeem]

You need to argue with the government, not Mercedes-Benz:-

Vehicle Certification Agency:-

My vehicle does not produce the same fuel consumption figures as shown in the 'New Car Fuel Consumption and Emission Figures' publication and/or the Internet site?

Because of the need to maintain strict comparability of results achieved by the standard tests they cannot be fully representative of real-life driving conditions. Firstly, it is not practicable to test each individual new car; thus only one production car is tested as being representative of the model and may therefore produce a better or worse result than another similar vehicle. Secondly, there are infinite variations in driving styles and in road, car and weather conditions, all of which can have a bearing on the results achieved. For these reasons the consumption achieved on the road will not necessarily accord with the official test results.

I appreciate that the official fuel consumption figures are obtained under controlled test conditions and as such may not be fully representative of real-life driving conditions. However, I am concerned that the figures achieved by my vehicle are radically different to the official figures?

You should refer to the "Driving your car: green tips" currently on Direct.gov - archived pages.


How is the fuel consumption test conducted?

The test is outlined in Directive 93/116/EC as amended by Regulation (EC) 692/2008, and provides results that are more than representative of actual average on-road fuel consumption than previous tests. There are two parts: an urban and an extra-urban cycle. The cars tested have to be run-in and must have been driven for at least 1,800 miles (3,000 kilometres) before testing.
Urban Cycle
The urban test cycle is carried out in a laboratory at an ambient temperature of 20oC to 30oC on a rolling road from a cold start, i.e. the engine has not run for several hours. The cycle consists of a series of accelerations, steady speeds, decelerating and idling. Maximum speed is 31mph (50km/h), average speed 12mph (19km/h) and the distance covered is 2.5 miles (4km).
Extra-Urban Cycle
This cycle is conducted immediately following the urban cycle and consists of roughly half steady-speed driving and the remainder accelerations, decelerations, and some idling. Maximum speed is 75mph (120km/h), average speed is 39mph (63 km/h) and the distance covered is 4.3miles (7km).
Combined Fuel Consumption Figure
The combined figure presented is for the urban and extra-urban cycle together. It is therefore an average of the two parts of the test, weighted by the distances covered in each part.

 

[Carabosse]

I take the urban figure and add 10%. Seems to work pretty well!

 

[Rory]

You need to argue with the government, not Mercedes-Benz:-

That true, but the cars are engineered to perform well in the tests. But you can't blame Mercedes for doing that - getting the emissions figure as low as possible is vital.

 

[grmc]

And today my "ECO" auto-cut out stopped the engine and I couldn't re-start it for over a minute, stuck at the lights with a queue of commuters behind me blasting their horns. Very embarrassing - and also annoying.

Now I've covered almost 2000 miles I have seen a small rise (2-3mpg) in fuel consumption, but the maximum I'm getting is 35mpg even on a sedate long drive, so I'm still feeling rather disappointed with the whole experience.

Another thing I've noticed is how much stone-chipping the wheels are succumbing to. I've never known paint chip so easily on the wheels of any car I've ever owned.

 

[Matt32AMG]

Reckon I'm lucky to see more than 18 to the gallon out of my slk32 around town. As for 25.2 mpg on a run...yeah right

But then if I was that tripped out by consumption, I'd have bought a VW Lupo or something similar

 

[Peterjackson]

I'm glad I am not the only one struggling to get sensible MPG figures in relation to the MB figures.

My 2013 C220 CDI has MB figures of 52.3, 74.3, and 64.2, but on runs that really ought to be considered extra urban I can only achieve 47.3. I used to get 50mpg overall out of my old E220 CDI, and my driving hasn't changed.

The local MB dealership are trying to do something about it, but they don't seem to know what I should be getting either. They seem to disregard the MB figures.

Peter

 

[survey]

I'm glad I am not the only one struggling to get sensible MPG figures in relation to the MB figures.

My 2013 C220 CDI has MB figures of 52.3, 74.3, and 64.2, but on runs that really ought to be considered extra urban I can only achieve 47.3. I used to get 50mpg overall out of my old E220 CDI, and my driving hasn't changed.

The local MB dealership are trying to do something about it, but they don't seem to know what I should be getting either. They seem to disregard the MB figures.

Peter

I wouldn't have thought that your figures are far off the mark!

 

[gizze]

I do think the sooner we move to the US style system of testing the better.

They seem to be figures that we all tend to achieve. Which would be nice.

 

[grmc]

I recently spoke to someone who works for an internationally renowned construction machinery company. He advised me that the European Directives on fuel consumption are so specific in what they require for emissions standards, that the manufacturers are now able to program their ECUs to show the leanest consumption on the tests.

Basically, in the test zones, the engines are doing the least work imaginable. This unfortunately leads to the incredibly misleading figures produced which are also a legal requirement to have with the sales information. Ultimately, the new emissions/consumption figures are impossible to replicate in the real world for the simple reason the engine only performs that way for the minutiae of instances that match those under which the EU tests record data.

I guess it's yet another side-effect of being part of the EU in that we're the unintended victims in ending up disappointed as a consequence of these ill thought out regulations we're all expected to follow.

I suppose a benefit is that in being able to fudge the data for the emissions, MB have managed to achieve a very low road fund licence tariff for the car, which goes some way towards recovering the loss in expectation of fuel running costs of the car. (However, this is not a real-world compensation, as the expectation was always to have low road fund licence costs AS WELL AS low fuel running costs - ho hum).