S90 real mpg

[Suziq]

Hi, i am thinking of buying an S90. Have test drove a pretrol and got 28mpg, then test drove a diesal and the trip was 17mpg. Both drives were on 30 and 40 mph roads. I was expecting the diesal to be higher than petrol. Does anyone know why this may be?

[Clan]

Originally Posted by Suziq

Hi, i am thinking of buying an S90. Have test drove a pretrol and got 28mpg, then test drove a diesal and the trip was 17mpg. Both drives were on 30 and 40 mph roads. I was expecting the diesal to be higher than petrol. Does anyone know why this may be?

you haven't given it a long enough test, and at 30 - 40 mph the car is nowhere near it's efficiency band, if you can get to 50-60 mph and stay there for a constant speed you will find it dramatically better over a longer distance. It will get thirstier if you go over 70 mph or use full throttle a lot too. Hills are no friend to economy, on the other hand cruising at 60 mph on a flat road will be in the upper 50's mpg with the diesel even more in some of the models is possible. You have to remember tyre pressures too which make a big difference , 38 psi...

[Ian0803]

Originally Posted by Suziq

Hi, i am thinking of buying an S90. Have test drove a pretrol and got 28mpg, then test drove a diesal and the trip was 17mpg. Both drives were on 30 and 40 mph roads. I was expecting the diesal to be higher than petrol. Does anyone know why this may be?

That does not sound normal for a diesel. The only way I could get that average on my diesel XC90, would be a cold start and drive it less than a mile.

On a cold start, 3 mile, 30-40 mph into town, it would not be difficult to get low to mid 30's on my XC90, so depending on how its driven, i would expect the S90 to be better

[bornmiddleaged]

How were you calculating the MPG?
If looking at the trip computer, you perhaps didn't drive long enough for it to recalculate the MPG.
How many miles did you drive?

For reference, I take brim to brim readings and when I am predominantly doing town driving, I am getting high 30s. Only a long run (e.g. Southampton to Edinburgh) I am getting mid 50s.
That is a V60 D4.

[Ulrikas PA]

Just a suggestion - take the 'Combined MPG' figures for each car and then knock off 10% or 15% if you do a lot of stop start town work.

I've had 104 cars and that formula always works for me as an average.

[Mad Malc]

There is something wrong with those readings. Did you reset the MPG trip on both cars before each test drive?
On average we get high 50s in our D4. That is with very little town driving. It is ridiculously economic for a big car.

[watto64]

If i idle our XC90 for any lenght of time from cold start up i get an indicated very low mpg however after a few miles of steady driving it rapidly rises, could it be that the dealer had the car idling away to warm up the diesel clatter?

One recent example was leaving a caravan site last week, whilst getting hitched up (so plenty of idling, forward/reverse etc) the trip read 9mpg, once on the move with 1900kg towing it settled at 26mpg.