Fuel economy - 2.0d

[fenton_jd]

Brimmed my tank to the absolute max sunday evening.

Drove to work monday morning - 30.7 mi
Drove home monday afternoon - 30.7 mi

Drove to work tuesday morning - 30.7 mi
Drove home tuesday afternoon - 30.7 mi

Fuel gage is sitting on the 1st bar after halfway. If the fuel gauge is to be believed

this seems excessive. It is not leaking either.

[Robbijay]

uh, I can't think of anything that'll make it use that much. How big is the tank?
My (70 L)fuel guage wouldn't have moved off the full mark at 124 miles!

[KFCKFC]

I have 2.0d V50 (2007) and am getting ~35 mpg on the trip computer; I do mainly urban. A rough calc based on a 52 litre tank capacity seems to indicate that you are getting ~20mpg which is not right; what is your trip computer telling you.

[Harvey1512]

Fenton - I don't have the trip computer so I work out my mpg the old fashioned way. During the summer I get between 46-48mpg no matter the types of journey that I do. Working on the basis that the trip computers are generally over generous you are seriously out of kilter. You haven't been driving in a Clarkson Top Gear style these last few days have you?

On a semi serious note could it be a dodgy tank of fuel? The only way is to use the tank and then fill up somewhere else next time and see what happens.

[chrisnjulie]

Doesn't sound right to me - our C70 2.0D returns around 45mpg on a run, and even on local running it doesn't drop much below mid 30's. Either your guage is telling porkies, or you have a problem. You'll be able to rule one out when the tank is brimmed again.

[civilservant]

Is your car an automatic?

I have a V50 (2007) and I must say the fuel economy is very poor compared to BMW, Audis and VWs I have owned. Depending on the type of driving I do, I can average anything from 38-42 mpg. Obviously the more urban driving I do, the lower mpg figure I get. I need to do regular motorway journeys to push the average up into the low 40s.

[fenton_jd]

Originally Posted by Harvey1512

Fenton - I don't have the trip computer so I work out my mpg the old fashioned way. During the summer I get between 46-48mpg no matter the types of journey that I do. Working on the basis that the trip computers are generally over generous you are seriously out of kilter. You haven't been driving in a Clarkson Top Gear style these last few days have you?

On a semi serious note could it be a dodgy tank of fuel? The only way is to use the tank and then fill up somewhere else next time and see what happens.

It's been like that pretty much for the entire year I've owned it.

Sitting at 80mph in 6th seems to be no better than sitting at 100 in 5th.

I dont do 60/70mph on the motorway, but even so I used to do 80-90mph in my old 1.2 grande punto and that was sensational on fuel despite having to be absolutely ragged to get it to 90mph.

My mum has a 2001 (before CO2 emmisions and MPG were invented) 2.0 144bhp petrol Vtec Honda accord which I did exactly the same journey in and fuel economy seems almost the same as that - i.e horrendous.

I judging this only by the fuel needle (which i know for a fact doesnt work properly 100% of the time). e.g the other day I put £10 in and it didnt even register it.

Sporadically I've started the car, and the needle has jumped to brim full, despite me knowing I have about £5 of fuel in.

I think I'm gonna sell tbh.

[s40_kid]

the best way to check is to refill and calculate your mpg the old fashioned way... that would give a true indication of consumption and possible issues? Is it serviced regulary? Does it have a relatively new a/f and oil? Are your tyres inflated correctly... i know these wouldnt greatly affect the mpg but it could all contribute together to give even worse mpg?

[Guru]

fenton, I believe the only thing that can give you such terrible mpg is a faulty O2 /lambda/ sensor in the exhuast, these cars have two such sensors btw, and both are situated in the exhuast somewhere in the vicinity of the catalytic converter unit.
Those sensors through the ECM govern the air/fuel ratio in the mixture entering the engine, and your car seems to be mega dosing on fuel.

They should have diagnostics, so a bit of code reading would be necessary. However i wouldn't be surprised if nothing turns up, but that doesn't always mean that all is in check...

[emmiller]

hi

newbie here

my wifes S40 is exactly the same and sensors where changed recently
MPG is really poor last 1/4 of the tank does roughly 50 miles give or take.

martin