320 cdi fuel consumption

[simon winn]

Hi,

This is related to my other thread but don't want to complicate it too much:

My 320 cdi (2001) is now returning 33 - 35 mpg on short hops - say 12 miles. Don't know about long journeys as I have recently started fixing an issue with air in the fuel lines.

My question is When I start the car from cold the computer has always re set itself and counts up from 20mpg. It takes ages - say 5 miles to creep up to about 30mpg. Is this normal or should it go stright to high 20's? Cheers, Simon.

 

[Alex M Grieve]

Hi,

This is related to my other thread but don't want to complicate it too much:

My 320 cdi (2001) is now returning 33 - 35 mpg on short hops - say 12 miles. Don't know about long journeys as I have recently started fixing an issue with air in the fuel lines.

My question is When I start the car from cold the computer has always re set itself and counts up from 20mpg. It takes ages - say 5 miles to creep up to about 30mpg. Is this normal or should it go stright to high 20's? Cheers, Simon.

Hi Simon,

I think this is normal. The instantaneous readout is always depressing over the first few miles - all the more so in cold weather. Once the engine is fully warmed through (and it takes longer with CDIs than other cars because of their efficiency) you will get more reassuring readings. If you then take it on the motorway, your faith will be restored!

 

[Rory]

My C270CDi is like that too - I really only use it for long journeys and it's 23miles to the motorway from my house.

It starts off around 30MPG and is generally just getting towards 40MPG by the time I get to the motorway and then it'll gradually inch up towards 50MPG over the next 100 miles.

If I haven't used it for a couple of weeks then I'll take it for a round trip (12 miles) into town to pick wifey up (so no parking and waiting) and it'll typically do low 30's on that run.

 

[undeckedhomer]

is your aux heater in the on position the switch that is in the ash tray if its in the on pos it will heat the car up faster then fule cmsupton get better and when at running temp turn it off

 

[simon winn]

Thanks for that guys - I think my fuel consumption is being affected by some air entering the high pressure side and am waiting for new pipes. On the subject of the auxillary heater I think this just operates a pump to heat the car quicker (I just changed the duo valve). If this is the case I don't think it can heat the engine up any quicker just the cabin? Anyone know any different?

 

[undeckedhomer]

aux heats the coolant on these cars turn it off and see when cold then on see how fast the car warms up??

 

[rothbury]

Hi,

This is related to my other thread but don't want to complicate it too much:

My 320 cdi (2001) is now returning 33 - 35 mpg on short hops - say 12 miles. Don't know about long journeys as I have recently started fixing an issue with air in the fuel lines.

My question is When I start the car from cold the computer has always re set itself and counts up from 20mpg. It takes ages - say 5 miles to creep up to about 30mpg. Is this normal or should it go stright to high 20's? Cheers, Simon.

You're lucky! the 2005 320cdi does the opposite starting at 40 and dropping.
Also I think that because of euro iv the mpg is a lot worse than previous cars.
My average over last 15000 miles is only 31.7 whereas Razoo in his 2004 model appears to be doing a lot better. My short hops don't ever beat 30.

 

[kirkyboy]

christ, mine starts at 16 and after 12 miles or so will be at 26-30 if lucky, i have e320cdi 2002, i got just 400 to full tank and that was taking it very easy, i have done 70 miles and my average over this is 26mpg again taking it easy this is a bit of motorway and town, on a 30 mile motorway trip maximum iswas 33mpg, is my car buggered please help me get better fuel consumption

 

[shaunevans1409]

Mm..... had my 2004 E320 CDi a month now and have only run a couple of tanks through her. Seems like I'm getting 31 mpg average, this being a mix of round town stuff and short hops of up to 15 miles. Mine seems to count up from 20 & climbs after that.

Any comments about consumption would be most welcome.

Cheers...........Shaun.

 

[rothbury]

Mm..... had my 2004 E320 CDi a month now and have only run a couple of tanks through her. Seems like I'm getting 31 mpg average, this being a mix of round town stuff and short hops of up to 15 miles. Mine seems to count up from 20 & climbs after that.

Any comments about consumption would be most welcome.

Cheers...........Shaun.

I think an overall average of 31 is about right unless you do all motorway especially if yours is Euro iv.

 

[jberks]

christ, mine starts at 16 and after 12 miles or so will be at 26-30 if lucky, i have e320cdi 2002, i got just 400 to full tank and that was taking it very easy, i have done 70 miles and my average over this is 26mpg again taking it easy this is a bit of motorway and town, on a 30 mile motorway trip maximum iswas 33mpg, is my car buggered please help me get better fuel consumption

70 miles with a steady throttle returning 26 - yes something is very wrong.
My daily commute is 100 miles - steadyyish on the way in and 'stuff it' on the way home normally. Add in a fair bit of queueing at each end and the fact I have to climb 1200 feet up over the pennies each way and mine ranges between 41 and 35 on the computer, plus a few local runs where the computer sits around 26. I get pretty much spot on 600 miles to a tank at the moment which works out about 35mpg average. A 320cdi should be worse than mine but only by maybe 2-4mpg.
A steady flattish run at 70 and I'd expect 45mpg - so you should see 40 easily. 400 miles to a tank, given it's an 80l tank, isn't good.
Have it checked.

 

[simon winn]

Since my car has had new injectors and thermostat it regulary gets 35 and once saw 40 mpg. I think I still need to set the injectors on a star but will wait till something else goed wrong. Also my aux heater (elec) is buggered but at £300 fot the element I'm not gonna bother changin - thats a lot of fuel