Fuel Tank size & Fuel gauge issue

dave_xsara · Post by **dave_xsara** » 06 Feb 2011, 11:45

Hi,

I've got a 2001 Xsara 90Hp Diesel. Can anyone on here inform me as to what the size of the diesel tank is on this car?

At the minute the car is showing just over 1/2 full on the gauge and the odometer indicating 189 miles since last refill.

Thanks.

dave_xsara · Post by **dave_xsara** » 06 Feb 2011, 11:52

Is it 60L tank?

If so, that would make the car averaging at 30mpg!

What could be going wrong here - I've tried different fuel suppliers and not noticed any difference in efficiency.

I did have the ECU replaced before Xmas could there be an issue there?

The current tank full of diesel came from Sainsburys. Now, I know they might not be as good as BP/Shell but would the efficiency be as low as 30mpg with their fuel?

I would not say I'm driving excessively hard on the car - I normally cruise at 2250rpm (predomiantly motorway driving) and only had a few runs at about 2500 - 2700rpm on this tank full.

Any advice appreciated.

wright · Post by **wright** » 06 Feb 2011, 12:20

the top half of the tank might be smaller than the bottom half, i had an e200 a few years ago that would cost me €70 to fill but to top it up from 3/4 of a tank would no more than €12

dave_xsara · Post by **dave_xsara** » 06 Feb 2011, 12:21

Surely though they would have factored that in with their fuel gauge?

wright · Post by **wright** » 06 Feb 2011, 12:29

i have never had a car where the top and bottom of the tanks were equal

wright · Post by **wright** » 06 Feb 2011, 12:34

you could have a leak or could be due a service, i change everything filters and oil every 10k, i did mine two weeks ago and it is much smoother and quicker after it, air and fuel filter make a difference to economy and power

Deanxm · Post by **Deanxm** » 06 Feb 2011, 12:40

If it starts and runs fine, and there is no derv smell i would say all is well.
Again ive never owned a car with equal volumes above and below the halfway mark.
My transit used to do 400miles per tank it would only do 25miles btween 1/4 and the warning light coming on though, other cars i have had will drop like a stone to the halfway mark and then cover 400miles on half a tank.

The only way to get accurate mileage is to brim it and run till the warning light comes on and brim it again, no fuel guage is accurate.

D

Xsarahdi · Post by **Xsarahdi** » 06 Feb 2011, 13:12

Xsaras have 54 litre fuel tanks.

dave_xsara · Post by **dave_xsara** » 06 Feb 2011, 13:33

There is a bit of smell (paraffin-esque) on start-up from cold.

The car is running Fate tyres @ 32psi front & rear. I'll also check it this afternoon to ensure that the brakes are not binding. Due to me doing mainly motorway miles they don't get much usage.

In terms of the gauge do the not calibrate it so that regardless of the tank shape the reading is a reflection of the amount of fuel in the tank?

I'll run it down to the reserve and work the mpg again from a larger sample.

What sort of figures should I be getting for mainly motorway cruising (60-65mph) using the manual 90bhp Diesel (It is one of the Xsra II shape cars, 2001 reg).

Thanks for all the input so far

P616VKX · Post by **P616VKX** » 06 Feb 2011, 13:50

I used to have a Picasso SX HDi 90... It used to average around 43-44 mpg on a run doing around 70-80mph...

However, the trip computer used to tell me all sorts of strange things, sometimes, 63mpg... And on the odd occasion, 99.9MPG...!

HDi engines, in my opinion, aren't all they crack up to be, but they're no where near as bad as some!

Anything under 40mpg is showing a requirement of some sort of service procedure being required. I did nothing to mind and gave it hell, didn't bother with it cos' I hated it severely... And it still worked out to nigh on 45mpg.

Post by **myglaren** » 06 Feb 2011, 13:56

Most fuel tanks have 'big bottoms' the lower part holding a significantly larger volume than the upper.

Very few gauges take this into account.

The only one that I know of is the one on my current C5, which is deadly accurate as can be seen from the distance covered in each segment of the instrument.
On my normal day-to-day I get 100 miles per sector, give or take 10% due to ruling conditions.

The only other one may have been my Renault 11 which had a very strange measuring device in the tank and a digital dashboard. Not certain about that one though.
It did pack up and it was more or less guesswork how much was in there and the speech synthesiser nagging on about low fuel all the time didn't help in the slightest.

Jaf · Post by **Jaf** » 06 Feb 2011, 14:19

My Xantia does 650kms on the first half of the tank and only 350kms on the second half. Bonkers.

nick · Post by **nick** » 06 Feb 2011, 17:13

The fuel gauge on the mkll Xsara is well known for being crazy unfortunately. There were endless complaints about them when the Xsara was a current model and Citroen released a software update which was only partially successful.

Some Xsaras seem worse in this respect than others, but I suspect your problem may well be a duff fuel gauge rather than actual high fuel consumption.

Post by **Paul-R** » 06 Feb 2011, 23:21

Our Xsara gets a regular 50mpg. It dropped to 49 during the cold spell and we can easily get 53/54mpg on a run. The fuel tank on the estate is 54 litres (very nearly 12 gallons) and I think the saloon is the same.

The fuel gauge is a bit, er eccentric but as I've said elsewhere I have my own benchmarks for fuel consumption. I always fill the tank to the brim and then note when the gauge moves off the full mark. Eighty miles means that I'm on target for 50mpg. It can be a bit erratic going to 3/4 but I' looking for 180 - 200 miles. Halfway should get 300 miles. The 3/4 mark should get 480 - 500 miles. I would hope to get to 540 - 550 miles before the warning light comes on and stays on.

2000rpm is an indicated 60mph on our carand when cruising I try to keep it to an indicated 60 or 65mph in order not to use too much fuel.