63 MPG! Well impressed!

[Countrykillen]

Not the most recent post but...
With my 2003 110HDI estate automatic i get about 6,77 l/100km (34,7 mpg I guess) in day to day driving and 6,0 l/100km (39 mpg)...

[stevewalsh]

My wife always gets around 61mpg out of our 2000 estate 90 manual, I usually get 51 mpg, I think I must have heavier feet

[PeterN]

My first one always used to be in the 60mpg region (unless my wife was driving it). Sadly the two I have now are only averaging around 50mpg although they will manage 60 on a long motorway run. I don't know if the computer was a bit happy on the first one or if there is something wrong with the others. Im going to do an injector leak off test when I get round to it.

Peter

[stevewalsh]

I found the computer to be spot on with ours, checked it over numerous fills, full to full, etc and always works out correct, It also runs out of fuel and stops when computer says 0 miles in tank..........
# Wife did complain that I should trust it, I wanted to see how far it would go when it said 0 left, the answer was about 3/4 of a mile. and a 2 mile walk each way to the garage.... Not heard the last of it and that was 3 years ago.......

[PeterN]

I think the speedo was a bit on the 'happy' side on that one but I didn't think it was that far out. The strange thing is both of the others are doing about the same, I only have one good MAF and have been swapping it between the two but it makes no difference apart from a bit more low down grunt.

Peter

[Doggy]

Surely you mean MAF?

[PeterN]

Sorry, yes I do.

[Welly]

HDi's seam to vary wildy in the MPG's, mine used to average high 30's and once when I really tried to get high mileage on a really easy flat route across Lincolnshire at an easy pace I only saw 53 and that was trying REALLY hard. Kinda gave up on modern dizzlers afterwards.

[PeterN]

Mileage 020.jpg

This was my best result.

Peter

[rwb]

Managed to get 1000 miles out of a tank on the 407 2.2 HDi. It's a slow job though, and everything has to work out just right -- the stars have to align.

Should be possible on the 406 Siemens 90 but the closest I ever got was 915.

[rwb]

70.jpg

[PeterN]

I find the temperature has a lot to do with it, it's always better in the summer anyway but the hotter the weather the better seems the consumption. Apart from the obvious less drag on mechanical components, when the air is hot it's less dense giving less drag, you can actually feel the difference, going down the Axminster bypass is just steep enough not to have to use any throttle, in the winter it hovers around 60 mph but when its really warm it will go up to nearly 70 mph if you let it.

Peter

[Welly]

You should try the murky world of a 5-cylinder petrol turbo engine.

26.5mpg!

It used to be 23/24mpg so has improved with age - nearly on 100,000 miles now.

To be honest there's not much point to it now considering you can make some HDi's churn out over 200bhp and still return good economy, I like the idea of Captain Jack's twin-turbo HDi with 213bhp.

[rwb]

The 407 2.2 petrol did 20mpg when used as a shopping trolley, but I got 46 out of it on my usual run.

It certainyl does depend on temperature. I offer the following two hypotheses:
(1) the car over-fuels itself when it's cold to try to warm itself up, and
(2) when the air is cold there is more of it in the cylinder and therefore the map allows more fuel to be injected.

[frog]

I have two other hypotheses to offer:

(3) Winter fuel has anti-freezing/-waxing/-clogging additives, making it less efficient
(4) Colder air is denser, giving more resistance while driving.