Wow got 67.1 mpg on the sports plus

[ioweddie]

(C220 cdi AMG Sport Plus Saloon Sept 2012)
Yep, was on a trip from the Isle of Wight to Sunninghill near Ascot, the reset from start was showing 51 mpg when I was doing 70ish mph on the M3, which was the average from start, so I reset it as though I had just started the journey while doing 70ish mph and the screen settled down at 67.1mpg for a while, mind you by the time I arrived in Sunninghill it was back down to 54. On the homeward journey I left it to its normal from restart setting it was 49.7 mpg which was probably about right for the average. Not bad as its only done 1450 miles from new and still need more miles to loosen it up. ioweddie.

 

[Markjames]

I have the same car on order, due to pick up next month. Looking forward to that sort of miles per gallon as seat exeo I'm currently driving struggles to average about 42 (probably not helped by fact it's a lease car and knowing it goes back soon not really been careful with it).

 

[Troon]

I reset it as though I had just started the journey while doing 70ish mph and the screen settled down at 67.1mpg for a while

...showing it doesn't take a lot of energy to maintain a steady speed, particularly if the "while" was downhill. In most cars, it allegedly takes about 20PS to hold 70mph.

The big killer for fuel economy is changes of speed: you burn fuel to get up to speed then turn all that kinetic energy into heat when you brake. Avoid changing speed by looking far ahead and anticipating what the traffic's doing and you can achieve better fuel economy.

You're right - you should see a big improvement as you get more miles on your engine.

This from my S211, hardly a svelte teardrop of a car, and not reset on the move:

 

[V12]

Will be good to hear a report after you've got a few more miles under your belt. I would expect much better figures personally.
Hope the "running in" does improve things.

 

[Red C220]

The OBC lies like a cheap watch.

See my tag below for real word numbers for a C220 cdi.

I do not do much motorway driving.

 

[Frugal]

I do about 60:40 highway/town driving and obc currently sitting at 60.1mpg average from new 17k miles ago. Best on a gentle run was over 80mpg. Saw significant improvement from around 5-8k miles which I guess is mainly due to (engine loosening up, warmer summer weatehr and summer deisel. I'm curious to see how this trends during the coming winter.

 

[Troon]

The OBC lies like a cheap watch.

Here's how much my OBC lies: http://www.mbclub.co.uk/forums/electronics/129722-trip-computer-mpg-accuracy.html

Cheap (quartz) watches are often better than expensive (clockwork) ones: but if I owned a watch that was 5% out (over a hour per day) it'd be going in the bin.

 

[Frugal]

Here's how much my OBC lies: http://www.mbclub.co.uk/forums/electronics/129722-trip-computer-mpg-accuracy.html

Mine's even worse - currently running around 8% optimistic since new but I've noticed the gap closing over time (only around 4% over last 7k miles) for some reason I can't fathom.

 

[chrisbin]

6k miles under the belt here and average is sitting at 37.7....a lot of this is short, stop/start journeys and if I do a longer journey with steady m-way cruising it improves a lot.

Generally I notice that its far more sensitive to conditions than my BMW's were - they would give the same sort of figure wherever/however you drove them.

For reference mine is an auto which, despite the official figures, probably doesnt help.

 

[V12]

For some reason my OBD was optimistic by 10% when I bought it. Never really fluctuated until I changed the wheels for slightly larger ones. Now the display is bang on the money. If it says 35mpg I really am doing 35mpg. There could be other factors at play here though, as the wheel change coincides with winter diesel, temperature drop etc.

Weird psychology behind it though. It always fealt great seeing 55mpg on the OBD in such a big car, now i struggle to see over 50mpg on a good run. 49mpg and 51mpg just seem worlds apart...

 

[Frugal]

6k miles under the belt here and average is sitting at 37.7....a lot of this is short, stop/start journeys and if I do a longer journey with steady m-way cruising it improves a lot.

Generally I notice that its far more sensitive to conditions than my BMW's were - they would give the same sort of figure wherever/however you drove them.

For reference mine is an auto which, despite the official figures, probably doesnt help.

I agree with your sensitivity point especially before coming up to normal temp compared to a couple of 3 series and an A3 Audi that I've driven previously. Also, re auto, I know the official W204 stats claim identical returns but I can never see how an auto box could match a manual in any real life situation other than M'way cruising.

 

[Red C220]

Here's how much my OBC lies: http://www.mbclub.co.uk/forums/electronics/129722-trip-computer-mpg-accuracy.html

Cheap (quartz) watches are often better than expensive (clockwork) ones: but if I owned a watch that was 5% out (over a hour per day) it'd be going in the bin.

Mine is over 10% optimistic.

I reset every tank, filled up today and brim to brim real world measurement 36.3mpg - OBC reading 40.2.

Been the same over 30 tankfulls and 14K miles.

I have no idea if it makes a difference but have the optional smaller 17" wheels on my Sport spec.

On the watch analogy, I have a Breitling Aerospace, that's a Quartz one.

 

[Dieselman]

On the watch analogy, I have a Breitling Aerospace, that's a Quartz one.

Don't forget to send it to Breitling when it needs anew battery.

 

[tali]

61.4 mpg is the best (laughable) figure for these -so to easily even beat that is witchcraft.

 

[V12]

61.4 mpg is the best (laughable) figure for these -so to easily even beat that is witchcraft.

Why do you presume that is the "best"/maximum figure?

Sent from my GT-I9300 using MBClub UK

 

[Frugal]

61.4 mpg is the best (laughable) figure for these -so to easily even beat that is witchcraft.

Sorry Tali, I don't understand your remarks - what do you find laughable and what witchcraft do you believe is being deployed here?.

 

[tali]

Why do you presume that is the "best"/maximum figure?

Sent from my GT-I9300 using MBClub UK

i don't presume - that is actually the best (extra urban) official/max figure

Sorry Tali, I don't understand your remarks - what do you find laughable and what witchcraft do you believe is being deployed here?.

Let me explain- the extra urban is laughable as in unrealistic -it is the Politicians promise , the 140 mph speedo on a boggo 1.6 car, the Nigerian email.
Yet this is the figure motorists rely on and then moan there car does "nowhere near that" .....and yet most of them easily beat the urban and combined figures -i have yet to find a motorist (other than moi) who has got less than official urban figure
So beating the figure which many believe is already grossly exaggerated is the "witchcraft element"
Personally, in over 20 yrs of driving 95% short urban journeys - all of my cars have got less than the urban figure

 

[wemorgan]

I genuinely thought when people quote a single figure for their car's claimed mpg people usually quote the combined cycle.

I know plenty of people who struggle to even reach that, but most often it's self inflicted rather than any fault with the car.

 

[V12]

i don't presume - that is actually the best (extra urban) official/max figure

Source for that info please.
That is not my understanding of the figures which are measurements.

Sent from my GT-I9300 using MBClub UK

 

[V12]

http://www.dft.gov.uk/vca/fcb/faqs-fuel-consumptio.asp

Sent from my GT-I9300 using MBClub UK