glc mpg problems

Isdyldan

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Have you had the fuel system emissions SW update done recently on a recall? I've noticed higher fuel consumption since it was done on mine.
 

Isdyldan

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Have you had the fuel system emissions SW update done recently on a recall? I've noticed higher fuel consumption since it was done on mine.

Actually, just to add to this - I wonder if I'm expecting too much of the car. There are many posts on many forums regarding MPG and whether it's motorway, town driving etc but I think average speed is vital to consider. I've been a bit disappointed with my 350 CLS average of 28 MPG, but only because I'm comparing it to the 29 MPG average for the same journeys in my old e39 BMW 530d. I guess I expected better being a newer car. However, the display is telling me that this is for an average speed of 19 MPH. That said, it's still worse that the 2001 e39!
 

Blobcat

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Newer cars can be worse because they generally weigh more and have more ecomentalism requirements that that mean they use more juice.

Also very much depends how you drive it, where and what the tyre pressures are like.
 

malcolm E53 AMG

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Newer cars can be worse because they generally weigh more and have more ecomentalism requirements that that mean they use more juice.

Also very much depends how you drive it, where and what the tyre pressures are like.

Quite agree, any improvement in engine performance in bhp per litre relative to fuel consumption has been negated by emission constraints, extra vehicle weight and of course those fashionable wide section tyres, 215 section tyres are quite adequate for most UK driving but most high end manufacturers are fitting 225-265 section tyres nowadays. If the eco warriors had any technical insight they would be campaigning against something like this which would make a difference, tyre manufacturers like it because of the profits to be made.
 

Taffy7hfa

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the newer generation of smaller cc, highly tuned, ecotech, ecoboost (call them what you like) engines seem to have a common characteristic of either running in fuel sipping super economy mode or flipping into tank draining performance mode. its how you drive them.
 

Isdyldan

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Quite agree, any improvement in engine performance in bhp per litre relative to fuel consumption has been negated by emission constraints, extra vehicle weight and of course those fashionable wide section tyres, 215 section tyres are quite adequate for most UK driving but most high end manufacturers are fitting 225-265 section tyres nowadays. If the eco warriors had any technical insight they would be campaigning against something like this which would make a difference, tyre manufacturers like it because of the profits to be made.

Yes - I think you're right here! Mine has 285 on the back for some reason.

I do think average speed should be mentioned more though when discussing mpg. Also, when people say 'combined' mileage I wonder if they mean 99 miles on a motorway and 1 mile in town?? Should it be 50/50?
I did a run yesterday of 51 miles which felt to me like quite a while of cruising at 60 mph on a duel carriageway. However it still said the average speed was only 28 mph, and average mpg 34.9. I don't know if this is good or bad.
 


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