XC90 D5 Trip Computer AVG MPG

[Clan]

Originally Posted by reggie59

I will provide long term details ( I have an app to record mpg) but long term, my trip computer says 31.4 and real mpg is 28.8.. Real? Well, knowing that the odometer is 5% optimistic, that another 5% less so about 27mpg

At 142p a litre of diesel...It is 23.7p a mile

Youd probably be better off with the V8 !

[RoyMacDonald]

Originally Posted by Clan

Youd probably be better off with the V8 !

Wonder if that would swing it with my wife?

[Clan]

they can be surprisingly economical .. upper 20's ... 30+ if you are lucky ..

[Ransman]

My XC60 computer is consistently 7% optimistic. The calculations will be done using a fuel-flow meter and the accurate ones over a wide range of conditions are very expensive but even the cheaper ones should get a better overall accuracy than 7%. Cynical old me thinks it's just a way that Volvo make you believe you are getting better mpg than you actually are.

There was a method of recalibrating on my previous Zafira but I haven't heard of one on the Volvo's.

[Clan]

No it is not done using a flow meter, it is done using data from injector opening time and fuel pressure and fuel temperature and distance travelled .
You used to be able to calibrate the fuel computers on volvos about 15-25 years ago , but it is deemed to be accurate enough now so that option doesnt exist any more .

[reggie59]

Originally Posted by Clan

they can be surprisingly economical .. upper 20's ... 30+ if you are lucky ..

lucky? I do not believe one second a 4.4 V8 would be more economical or even slighly less economical. The official combined of the v8 is 20mpg. People who say the v8 does 30mpg are people who are trying to flog their v8.

We have a 2.5 v6 auto petrol, official combined is 23mpg...it does 18.8mpg (minus 5% odometer...)

[Clan]

Originally Posted by reggie59

lucky? I do not believe one second a 4.4 V8 would be more economical or even slighly less economical. The official combined of the v8 is 20mpg. People who say the v8 does 30mpg are people who are trying to flog their v8.

We have a 2.5 v6 auto petrol, official combined is 23mpg...it does 18.8mpg (minus 5% odometer...)

I'm saying the V8 Can do 28-30 mpg and i have done so , it is the worlds cleanest V8 hence fuel efficient see my signature below .. If you drive it without consideration for fuel consumption then it has the possibility of horrendous fuel consumption of course .
The official fuel figures do not imply you should or will get the stated figures , it is purely government figures obtained on the same equipment to compare different makes and models .

[262coupe]

I'd like to add my contribution to this as I owned an xc90 V8 for 2 years until I traded it in for an D5 200hp Exec. The fact is the V8 is a lot more efficient than you might think and the D5 less so. I used to easily be able to get 26-28 MPG from the V8 and 30 was just about possible being super careful. The average of 'normal' driving and for me that meant 85 on motorway and the occasional blast from the lights to enjoy that fantastic growl, was 23 mpg. The D5 in contrast in 'normal' driving gives about 29, driven carefully I get 34 and in super careful mode I have once got 40 but that was literally 60 on cruise on a long run. Towing is a similar story with a big caravan V8 - 16-18.......D5 21-23.

In short if you bear in mind the difference in cost of diesel to unleaded the V8 is utterly brilliant. The only reason I got rid of mine was the worry about the balance shaft failure of the V8 seen in the states. The D5 is fine but I really miss that effortless smooth power of the petrol powered beast!

[reggie59]

Originally Posted by Clan

I'm saying the V8 Can do 28-30 mpg and i have done so , it is the worlds cleanest V8 hence fuel efficient see my signature below .. If you drive it without consideration for fuel consumption then it has the possibility of horrendous fuel consumption of course .
The official fuel figures do not imply you should or will get the stated figures , it is purely government figures obtained on the same equipment to compare different makes and models .

exactly. So, let me be spectical when someone tells me that a car which does 20 mpg on the official combined can do 28-30 mpg.

Put simply, I do not believe it. I drove a few cars in my life and never never o
achieve official mpg... So 10 mpg better ? 50% better?

Again, to my experience, you are more likely to get close to official combined in a diesel.

Incidentally, drop my speed to 60 on motorway last week. Refilled this morning and on a brim to brim, achieved 33.6!!! is it the official combined on the d5 185? Hurray!

[Clan]

The "official" figures never claim to be those you will get on the road , in fact there is a disclaimer on the official literature , they are published just so that you can compare the fuel consumption of one car ( any make or model ) against another ( any make or model )