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Gary_W
29-01-2010, 10:57 PM
Hi all,

I know this has been discussed before, but I'll have another bash if there are any takers :)

My new 2.0 TDIe has a quoted fuel economy of 48.9 MPG 'extra urban' which to me means 'traffic' and 'stopping and starting a lot'. At the other end of the spectrum, it's quoting 74.3 MPG 'extra urban' which to me means an ideal run on a motorway where you are doing 60 ish and do not have to slow down or speed up. Obviously not going to happen in the UK...

So I feel that my 'average' economy should be somewhere between the two. Not being unreasonable is it?

Why, then, when I've stuck at 70mph max for the first tank, is my 'average' economy quoted as 47mpg? The DIS proved accurate as I filled up and did the maths. Admitedly I'm still getting used to driving a diesel vs a petrol, but I'm keeping the revs nice and low and changing up like a good boy when advised to do so. Today, I was in traffic across town and it returned 31.7mpg. This was using the stop start and accelerating carefully.

Is this likely to improve with age and the warmer weather, or do I have a fault? Or is this just the way it is? Can't believe it's the latter as there is 'optimisitic' and then there is 'a lie' and this is falling into category 'B' so far.

Loving the thing dearly apart from the economy, though :)

Gary

rharris
29-01-2010, 11:37 PM
I don't have the same car, but my previous a6 1.9 tdi used to give me 41mpg for stop/start driving and 50+ on the run. So yours definitely sounds off!

satsu
29-01-2010, 11:41 PM
Here are definitions: http://www.vcacarfueldata.org.uk/information/consumption.asp

If I do a long, steady A-road run and take great care to accelerate gently and avoid braking then I do get close to the extra-urban figure. Mine has improved gradually over time - probably me adjusting to the car (my first diesel too) as well as the car loosening up. Since about 10k miles I've got 38-40, which compares pretty well to the quoted combined figure of 41.

Based on that, I'd say give it a bit of time and see how it is once you and the car have got used to each other and (as you say) the weather has warmed up a bit.

SUNNYJIMS
30-01-2010, 12:37 AM
Hi
think from experience with past cars youreconomy should improve(had proper reps mondeo 2L TD 04 reg with 150K on clock and after 25K economy and performance improved by 15%) just bought A4 Avant TDI 130 sport (116K) and drove to swanage and back(400miles) on £25.00 of fuel (70mph max going 60mph return) arrived home with about 60 miles of fuel left indicated so pretty reasonable but deadly boring -wife impressed though as she wasnt convinced would be more economical than Fiesta 1.4 zetec we have-terrible economy for small car

robtt09
30-01-2010, 02:30 PM
My 3.00tdi economy has dropped about 10% with the cold weather . It has now got nearly 13k on the clock and I have noticed it has become smoother and quicker past the 10k mark.I oten give it a shot of cetane enhancer (Millers) and that does give a bit better mpg and probably cheaper that filling up with BP Ultimate diesel tankful

rharris
31-01-2010, 12:50 AM
I thought the audi manual states not to use an fuel additives; I have done in previous cars just flush things out once in a while - am I being over cautious by not doing the same with this lump?

A1287210
01-02-2010, 09:43 AM
Just drove to Glasgow and back at the weekend 70-80 ish on the motorway and a tank did 590 miles averaged about 45 mpg. I must admit I have noticed a drop off in mpg after my service and oil change.

Damo

Gary_W
01-02-2010, 10:47 AM
Thanks for all the replies - I'll keep an eye on it and see how it goes... I think to get anywhere near that top quoted figure you really need a flat, clear road with ideal conditions and to be able to do 56mph without touching the throttle or the break for about 300 miles. Then you might get there :)

For me, if I can average mid 50's then that'll do nicely for a car of this kind of size and quality.

Gary