Surprising MPG

Dr Who · 17 Aug 2012 at 12:30

Okay, so I probably shouldn't be surprised, but I never bought the CLK for fuel economy, only to be a comfortable commuting car which returned better than my Impreza.

Done a few mixed journeys, m'way, town and A-road, and the car has been Averaging 35mpg, which for a car that is supposed to do 37.2mpg Extra Urban impressed me greatly, after all I have not been driving it like a saint. At the end of the day it is a 14 year old 3.2 V6 which is pretty heavy and was expecting a mixed mpg return of around 28mpg.

Anyone else achieved some surprising mpg results with their cars? Either good or bad

[TW]Fox · 17 Aug 2012 at 12:33

Thats very suprising especially as the Merc V6's are not exactly reknowned for being efficient, infact its something they were traditionally poor with in comparison to the competition.

To average 35mpg on mixed driving from a car which has an urban figure of only 37mpg is very bizarre, enough to make me question the accuracy of your figures.

paradigm · 17 Aug 2012 at 12:34

The fact that on a mix of town and A-roads I get 37MPG average over the course of a weekday in my remapped 2008 A6 2.0T FSI (not a light car by any stretch!), and over 42MPG on a decent motorway run (such as down to Dover), has left me quite surprised.

It's not far off the economy of my old 330d.

Basher · 17 Aug 2012 at 12:35

I am surprised at how efficient my Z4 is. Currently sitting at about 37mpg thanks to mostly motorway miles.

[TW]Fox · 17 Aug 2012 at 12:36

paradigm said:
The fact that on a mix of town and A-roads I get 37MPG average over the course of a weekday in my remapped 2008 A6 2.0T FSI (not a light car by any stretch!), and over 42MPG on a decent motorway run (such as down to Dover), has left me quite surprised.

It's not far off the economy of my old 330d.

But the key difference here is that the official figures for your car would indicate this sort of impressive economy is possible - his would not.

I also often get nearly 40mpg on long runs in my 530i but given this pretty much matches the Extra Urban figure its less suprising than you might think (Yes, yes, I know Extra Urban isn't a motorway test but generally you tend to be able to acheive the Extra Urban figure if you have a long motorway drive).

paradigm · 17 Aug 2012 at 12:37

[TW]Fox;22581300 said:
But the key difference here is that the official figures for your car would indicate this sort of impressive economy is possible - his would not.

No it wouldn't, extra urban suggests 37MPG (6.5l/100KM), and average would suggest 28MPG (8.2l/100KM).

Skilid · 17 Aug 2012 at 12:39

[TW]Fox;22581300 said:
But the key difference here is that the official figures for your car would indicate this sort of impressive economy is possible - his would not.

I also often get nearly 40mpg on long runs in my 530i but given this pretty much matches the Extra Urban figure its less suprising than you might think (Yes, yes, I know Extra Urban isn't a motorway test but generally you tend to be able to acheive the Extra Urban figure if you have a long motorway drive).

Interesting. I've always found that with my cars the urban figure is pretty accurate but on the motorway I only manage to achieve the combined figure unless I slow right down to 50mph. Only then can I get anywhere near my extra-urban figure. Still never hit it though.

[TW]Fox · 17 Aug 2012 at 12:42

paradigm said:
No it wouldn't, extra urban suggests 37MPG (6.5l/100KM), and average would suggest 28MPG (8.2l/100KM).

The extra urban figure of a 4 cylinder A6 2.0TFSI is less than the same figure for an older 6 cylinder 530i?

Really?!

Edit: No, not really. Official figures for a 2008 Audi A6 2.0TFSI Avant are as follows:

Direct.gov said:
Imperial Urban (cold)25.7
Imperial Extra Urban44.1
Imperial Combined34.9

So, I stand by what I said. Your figures are good - but inline with what the figures would lead you to expect. The OP's are miles out.

Jono8 · 17 Aug 2012 at 12:45

i thought the mixed figure for a 2.0 TFSI is generally ~35-37mpg depending on the car.

[TW]Fox · 17 Aug 2012 at 12:45

Jono8 said:
i thought the mixed figure for a 2.0 TFSI is generally ~35-37mpg depending on the car.

It is, I've no idea what paradigm was on about.

Dr Who · 17 Aug 2012 at 12:45

[TW]Fox;22581272 said:
Thats very suprising especially as the Merc V6's are not exactly reknowned for being efficient, infact its something they were traditionally poor with in comparison to the competition.

To average 35mpg on mixed driving from a car which has an urban figure of only 37mpg is very bizarre, enough to make me question the accuracy of your figures.

I agree, that is what is so surprising, I can only think that the 2 motorway journeys combined have pushed up the element of extra urban mpg in the mix.

My calculation was based on total cost of fuel/cost per litre/4.546 = gallons used divided into the total mileage between fills.

I cannot think what I may have done incorrectly, but I am all ears (this has been done over 2 tanks of fuel and has returned the same figures on both tanks). I can accept one might be a miscalculation, but 2 fills of fuel?

Jonnycoupe · 17 Aug 2012 at 12:47

How accurate is your speedo / odometer?

paradigm · 17 Aug 2012 at 12:48

[TW]Fox;22581357 said:
So, I stand by what I said. Your figures are good - but inline with what the figures would lead you to expect. The OP's are miles out.

Hmm, didn't think to look for government figures, I just searched for the figures and that's what I found.

typk · 17 Aug 2012 at 12:48

Currently getting 36mpg in my Ep3 type r. Very surprised, go into vtec multiple times a day. No motorway driving either, must be driving it wrong.

Dr Who · 17 Aug 2012 at 12:53

[TW]Fox;22581357 said:
The OP's are miles out.

Well they are between the average (28mpg) and the extra Urban (37.2mpg) so hardly miles out.

I will acknowledge that there has been a markedly more m'way and dual carriageway, but I would be surprised if it was all m'way and it got to 37odd.

I have used exactly the same method to measure mpg for years, which is why I always fill my tank and do the calculations, I did it over 2 tanks with similar journeys. The previous fills have been all urban and it has returned @22.mpg over those, which is around what I would expect.

Accuracy of odometer? Well the route planner has matched the mileage my odometer has increased over planned journeys to within a mile.

[TW]Fox · 17 Aug 2012 at 12:57

I suspect then that the 'urban' usage was very little, in which case it makes more sense. Especially as you know you get 22 around town, it wouldnt take many miles @ 22 to drag that average right down.

Dr Who · 17 Aug 2012 at 13:04

[TW]Fox;22581481 said:
I suspect then that the 'urban' usage was very little, in which case it makes more sense. Especially as you know you get 22 around town, it wouldnt take many miles @ 22 to drag that average right down.

I agree, it was the much smaller element, but I am more surprised by the fact it is a 14 year old, presumed very uneconomical car which is getting close to its official extra urban figures. The surprise being that it must still be in a very good state of tune.

The mix of miles I have done recently was Street to Cardiff centre and back, and then Street to Axminster and back. so town miles about 10 out of 265 and A roads (dual and single carriageway) about 110 out of 265.

But like I say, the biggest surprise is not the vicinity to official figures, as I often achieve that in my cars, it is the fact that it is an old car that can still get close to official figures.

Firestar_3x · 17 Aug 2012 at 13:05

Very impressive, how many miles has it done?

Dr Who · 17 Aug 2012 at 13:06

Firestar_3x said:
Very impressive, how many miles has it done?

74,100 so far.

Dogbreath · 17 Aug 2012 at 16:35

Tizzer said:
Currently getting 36mpg in my Ep3 type r. Very surprised, go into vtec multiple times a day. No motorway driving either, must be driving it wrong.

I managed 36mpg in my EP3 as well, and numerous people suggested it wasn't possible unless I was driving like a granny