What Car True MPG survey

[E280wilson]

Just got the usual email from What Car and one of the articles is about true MPG. How can they be so far out and why don't the regulators make the manufacturers change the way there tested.

Here's a couple of them. The rest can be found here.
Real-world MPG: Most economical executive cars - What Car?

2. Mercedes C300 Hybrid - official 78.5mpg: True MPG 57.8mpg

The Mercedes C-Class has been fully reworked to take the fight to BMW in the mid-size executive class. If your priority is ultimate handling and chassis balance, then the 3 Series is still the best. Alternatively, if you are swayed by cabin finish, then you’ll be hard-pressed to fault the C-Class’s beautifully built and stylish cabin. The hybrid model falls more than 20mpg short of its official economy, but it is still the second most efficient saloon of this size that we've tested.

5. Mercedes C200 Bluetec AMG Line – official 72.4mpg: True MPG 55.0mpg

This isn't the only Mercedes C-Class on the list, which says a lot about the new saloon. If you opt for the Airmatic suspension you'll get a limo-like ride at speed and good handling. Unfortunately, while efficient, the 1.6-litre Renault-sourced diesel sounds gruff and needs to be worked hard to make decent progress.

 

[johns E350]

It is no surprise
But you even get people on here claiming stupid mpg figures do people really expect us to believe such b+ll s++t

 

[boxbrownie]

Just got the usual email from What Car and one of the articles is about true MPG. How can they be so far out and why don't the regulators make the manufacturers change the way there tested.
.

Because the regulators TELL the manufacturers how they should test the vehicles!
How many times does this need to be told.......its the test regime laid out by the EU that determines how the test is carried out.

I know from personal experience that the Director of Global Vehicle Evaluation and Verification testing of the largest manufacturers facility in the UK has actively lobbied the authorities for years now to get a change in the procedures, as they just do not reflect real world consumption, it does no one any favours when the shiney new car Mr Anybody bought fails to achieve any where near published figures.

Moan at the regulators.....not the manufacturers.

 

[henley]

It was the regulators who set the parameters for MPG testing, (i.e. the EU). Every manufacture is forced to test with exactly the same procedure.

Real and true MPG experienced is down to something quite fundamental.
A. At what engine temperature do you start the measurement. Diesels will not be efficient until max operating temp is reached, fuel consumption is not good until that temp is reached.
B. What gradients are you mainly negotiating when trying to observe true MPG.
C. What speed and accelerations are being adhered to when trying to observe true MPG.

Fact...if you look at your true consumption, after fully warming up and while driving on a level road with a steady low throttle opening, you will see manufactures claimed MPG figures. Once the variables come into effect as in A, B C, above, then you get actuals, not really rocket science.
And then even real and true MPG will vary a lot depending on the driver, so manufactures claims can never get close to a normal or even abnormal day out on a run.

 

[merc85]

i always brim the tank reset the trip, then brim the tank again to get my mpg figures

 

[geraldrobins]

Ive always achieved within 10% the official combined figures. but no journey is the same and we all drive differently.

 

[geraldrobins]

It is no surprise
But you even get people on here claiming stupid mpg figures do people really expect us to believe such b+ll s++t

Bit harsh!!! Some may have used obc figures or mis-calculated but I suspect most posts were made with honest intent

 

[johns E350]

Bit harsh!!! Some may have used obc figures or mis-calculated but I suspect most posts were made with honest intent

Firm but fair

 

[dozypillock]

i always brim the tank reset the trip, then brim the tank again to get my mpg figures

I tend to never fill more than half a tank for general day to day driving, as do not do many miles. I do not know what petrol weighs, but I feel sure a full tank is like carrying round a couple of extra passengers all the time.
I only fill up when I know I am going on a long run.

Neil

 

[The _Don]

I tend to never fill more than half a tank for general day to day driving, as do not do many miles. I do not know what petrol weighs, but I feel sure a full tank is like carrying round a couple of extra passengers all the time. I only fill up when I know I am going on a long run. Neil

1 litre of fuel weighs 0.73722kg

Not sure the exact size of tank but say 60 litres 60x0.73722kg = 44kg roughly

 

[gIzzE]

You could argue that it is the ignorance of owners that mean the figures are so far out of course?

 

[John]

It is no surprise
But you even get people on here claiming stupid mpg figures do people really expect us to believe such b+ll s++t

Bull is not offensive...

 

[dozypillock]

1 litre of fuel weighs 0.73722kg

Not sure the exact size of tank but say 60 litres 60x0.73722kg = 44kg roughly

Probably not as heavy as I thought. Suspect around a 12 gallon tank?
According to the computer I got the best MPG so far on Saturday, doing 180 mile round trip to the Gemclean event, and averaged 26.2 MPG at a steady 90-95 (oops, I mean of course 65-70 as would never speed).

Neil

 

[Bri]

More lies

What are they saying...... Mercedes telling us lies......what next they will tell us they don't rust.

 

[gIzzE]

Drive at an average of 39mph on a warm engine and you might hit the combined mpg figure, drive any faster or start your car from cold and it is going to be very tricky.


Just look at the USA websites to get a more realistic figure for MPG, but remember to convert back to imperial kids!

 

[Ricky16]

I've avg 16.8 over the last 1200 miles that's combined

 

[Dieselman]

I tend to never fill more than half a tank for general day to day driving, as do not do many miles. I do not know what petrol weighs, but I feel sure a full tank is like carrying round a couple of extra passengers all the time.
I only fill up when I know I am going on a long run.

Neil

You can't do many miles at all, I did three full tank fill of diesel in four days a week ago.

 

[gIzzE]

Look at the E250 diesel.

US figures...
33mpg city
50mpg highway

UK figures...
48mpg urban
57mpg combined
65mpg extra urban



Which customer is going to get his knickers in a twist?

 

[geraldrobins]

Drive at an average of 39mph on a warm engine and you might hit the combined mpg figure, drive any faster or start your car from cold and it is going to be very tricky.


Just look at the USA websites to get a more realistic figure for MPG, but remember to convert back to imperial kids!

I can hit the combined figure on a warm engine at 20degrees driving 75-80 on the motorway

 

[MUGGY]

Look at the E250 diesel.

US figures...
33mpg city
50mpg highway

UK figures...
48mpg urban
57mpg combined
65mpg extra urban



Which customer is going to get his knickers in a twist?

Correct me if I'm wrong but a US gallon is less than an Imperial gallon.