Talk Morgan Forums Community The Malvern Arms Real World Fuel Consumption vs Official Figures

That is very impressive for a 3Ltr you must be very pleased with the change.

The only car I've ever owned that achieved the manufacturer's claims is my 4/4.
My worst was a bmw mini cooper s which had a computer telling me I was getting mid 30s when I was actually lucky to get 21 or 22.
Nick

Something which you need to bear in mind when comparing fuel consumption figures for diesel cars . You need to take into consideration the time of year- not what you think - our clever friends st the refineries produce a different diesel for winter to that of summer.

The composition of the winter fuel is designed to provide more reliable starting & initial running during low temperatures, this sacrifices a bit of MPG , My typical summer mileage for a 2.2 diesel is 41-42, during the winter this drops to sub 40, another contributary factor is the longer warm up times. I imagine all the manufacturers figures omit the warm up cycle.

The AMG C43 can achieve 32mpg in real world Motorway / A Road driving, but only in "Eco Pro" mode, which chases the highest gear and has an "Auto Coast" feature.
Sounds OK, but Mercedes claim 44.1....

The Plus 8 averages 25mpg but can be pushed to 30....and I really do not care. It is simply worth it...

Contrast that with the 10 year old CLC 180 "Kompressor", Mercedes claim 42 mpg and on the motorway that is easily achievable, over the last 10,000 miles it has averaged 34mpg. But the car tax is more than the C43.
Go figure?

Yes.
But the 4/4 fuel log is in the car and I'm not going out to the garage.
The Z3's (1.9ltr) log is electronic on my tablet - worst just under 30mpg, best just under 38mpg.

The official figures for the family merc C200 is 46.3 and the actual over 85000 miles is 47.8. Pretty close.

Got to be said its never driven in sports mode ( is there really such a thing on a 2 litre diesel family snotwagon?) and usually like Mother Teresa would do. After all, its not a machine to get the blood flowing is it?

The Fezza did 16mpg driven gently. I never even looked at the official number

That is astonishing, were you driving it like you stole it or reasonably ?

I got 37.8mpg actual consumption on my Audi while the computer noted 43.2mpg average consumption for the last 13.000km. Some 15% difference car-computer versus actual.

If being proper geeky don't forget to measure actual distance driven and not the variable rolling circumference calculated.

Cars over read as a matter of course of speed, that only gets worse as tyres wear down.


Even when done by brim to brim distances travelled are inaccurate unless you log actual real distances accumulated.

I used to have a sat available distance travelled based fuel economy tool on my older 1690T garmin sat nav, the closest distance tally was the mog!

The 4/4 must be my most economical, but nothing beats the Ferrari. It cost about £100 to fill the tank and the first quarter tank lasts well over 200 miles, even when driven swiftly, it’s an engineering marvel!


Sadly, the next three quarters of the tank only does about 100 miles,