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jds68
21-01-2017, 05:02 PM
Just getting to know my A4 (S line 190 S tronic) since getting it in December and wondered if anyone else has one with the larger 54 litre fuel tank but struggles to get anywhere near that much fuel in it?

For instance, I filled it up from a quarter full and it only took about 35litres, was expecting more like 40 (0.75 x 54) so I thought I'll let it get lower next time.

So I let it get to when the red light comes on and you keep getting messages about being dangerously low on fuel, and can it take you to the nearest fuel station etc. and then I filled it up again. This time it took about 43 litres, so still 11 in the tank presumably!

This seems like the gauge is unnecessarily cautious. Obviously some safety factor is good, as you wouldn't want to run out the moment it indicated empty, and I would never let it get that low in any case,
but it just seems that in order to take advantage of the larger tank you would have to drive with constant low-fuel warning lights on and reminders all the time, which would obviously discourage this.

I was expecting the red light to come on the gauge when there was about 6 litres left, still enough for 50-60 miles, although they would perhaps be tense miles! The other issue with this is the fuel gauge is a digital led segment thing, lovely to look at and all that but not so practical. The segments stay lit for quite a while then a whole chunk goes, unlike with an analogue gauge where you can judge it more precisely and have more of an accurate idea of remaining fuel.

I should point out I am adjusting from a previous B8 A4 with a 63litre tank, and I fairly often do long journeys so a decent range is a must, hence why I wanted the 54litre tank in the new one and not the comedy 40litre!

xtremist
22-01-2017, 10:44 AM
I have found exactly the same with my A4 (with larger fuel tank). When the display shows I have a range of less than 50 miles, the tank more than often only takes approx 45 litres to fill. In 27k miles, I have only twice had to put over 50 litres in the car and once managed to squeeze 54 litres into it (I must have been feeling very brave that week).

jds68
22-01-2017, 12:47 PM
You're way braver than me then to get upwards of 50 litres into it! Even 54...the range must have been in single digits...

xtremist
22-01-2017, 06:09 PM
You're way braver than me then to get upwards of 50 litres into it! Even 54...the range must have been in single digits...

It was flashing at me a fair bit and I couldn't cancel the warning! Think it said zero range for about 20 miles before I re-filled it. I do like playing fuel gauge roulette ;-)

cowcatcher
22-01-2017, 11:11 PM
I have the 54 litre tank but haven't refilled from empty yet, but what I have noticed is that the range when full is only about 350 miles. I will monitor and report back


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jds68
24-01-2017, 11:57 PM
Your long term trip computer will give you the average mpg, but in any case if you only have 350 miles range at full on 54 litres that's only about 29.5 mpg!

xtremist
25-01-2017, 08:17 PM
For info, I generally get approx 550 - 600 miles per tank with an Stronic 2.0 diesel. Roughly 53 mpg (see fuelly link below).

jds68
25-01-2017, 08:25 PM
Currently I'm getting more like 50 average, range on fill up says about the same as xtremist - also a 2.0 diesel s tronic.

All depends on what type of traffic/roads and how you drive. I always find the winter is the worst time of year for everything to do with driving, especially economy though!

cowcatcher
25-01-2017, 09:30 PM
600 ish miles on the clock and the long term readout is showing mid 40's mpg. I filled it up today and the miles to empty was showing 510, so I guess this improving as the car has more history to work from and the mpg improves

My commute home was 51 mpg


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satsu
27-01-2017, 12:11 AM
The range is based on more recent driving, rather than the long-term average. I can't find a figure in the manual but for the B8 it was the last 30km. My range on filling up generally varies from about 500-565 because of this but sometimes dips if I've spent a lot of time stuck in traffic, especially with a cold engine

MarmiteSandwich
23-02-2017, 06:34 PM
I had this very problem with a new Avant in July 2016. Ordered the larger tank (and larger Adblue). Within a week I was onto the dealer to say that the 54L tank hadn't been fitted. They sent me the manufacturing schedule from Germany to prove it had! I think that basically the range calculation algorithm isn't correct for this tank.

After a few tankfuls, the calculation settled down to the following misleading pattern:
- after a refill, the range is c640m;
- if you monitor the elapsed miles plus range miles, it will gradually dwindle from 640m to about 550m;
- the warning will come on at about 480m;
- the range will be zero at about 550m;
- if you refill when the range has reached zero and you use the average consumption (55mpg in my case) you will see that you actually had about 50m left.

So basically I add 50 to the range when I get below about 100m. The full tank range is c600m.

For a high tech car (Vorsprung etc.), I find this behaviour very frustrating. I once had a Vauxhall and took the range down to zero, which I found to be exactly right! I also find many of the A4 tech features to be substandard, either faulty or poor ergonomics, compared to cheaper mass produced vehicles, which you typically get when you rent. I am thinking of the satnav, audi connect, the media player etc. See elsewhere.
Marmite

noscream
24-02-2017, 12:32 AM
Your long term trip computer will give you the average mpg, but in any case if you only have 350 miles range at full on 54 litres that's only about 29.5 mpg!

Thats me, but it is the 3.0 V6 272 TDI. I get around 350 miles to a tank but I do 90% city to city A roads.
If you have the 2.0 you should get better than my 272 V6.

I got the fuel warning on & got £61 into the tank with 50 miles showing remaining. (around 51 litres).

jds68
24-02-2017, 09:59 AM
And of course yours (3.0 TDI Quattro) has the 58 litre tank...

I think from the earlier comments with the 2.0 if you can get 51 litres into the 54 litre tank the range is definitely on zero.

a1dmo
24-02-2017, 12:19 PM
I have the 1.4T avant and when i fill up it shows my range to be around 460-480
I actually get around 340 when the computer is showing 10 miles left
This seems pretty poor
my long term memory (around 3500 miles) says im averaging 34mpg
What are other people getting in their 1.4t?
Thanks