07 tdci econemy

[gobba]

hi i am just wandering what all your mpg is..  i have only had the car two week. when i purchased it the mpg was on 42.. every day it is dropping and now im currently on 38.7 mpg,, from what i have seen i should be getting a lot more.

[FatHead1979]

27 minutes ago, gobba said:

hi i am just wandering what all your mpg is..  i have only had the car two week. when i purchased it the mpg was on 42.. every day it is dropping and now im currently on 38.7 mpg,, from what i have seen i should be getting a lot more.

What kind of journeys are you doing and have you reset the MPG counter since you got the car?

[isetta]

the only way to do it properly is to fill tank to brim. note mileage. use up most of fuel, fill tank to brim again. divide mileage between first and second full to brim fill up by the amount of fuel you put in on the 2nd fill (1 gallon = 4.54 litres).  This is the only way that has any accuracy. 

[south_bound]

2 hours ago, isetta said:

the only way to do it properly is to fill tank to brim. note mileage. use up most of fuel, fill tank to brim again. divide mileage between first and second full to brim fill up by the amount of fuel you put in on the 2nd fill (1 gallon = 4.54 litres).  This is the only way that has any accuracy. 

+1 on this method - the display figures are just not reliable.  My mpg on a similar age car (but the 1.6 tdci) just keeps getting better and is now consistently up in the 60s to 65s with mainly A road and motorway driving at reasonable speeds.  It depends on the type of driving you do and also needs good regular servicing and I definitely saw an improvement with a remap and egr deleted from the system so you might consider that.  And I over inflate my tyres to about 38psi to reduce rolling resistance.

[gobba]

its all up to date on services, new cam belt etc, this week i have changed a blown boost pipe, glow plug,, they were no good. main driving is just school runs so it is a lot of stop start but i am not using any heavy acceleration. i will have a look at tyre pressure and i am concidering  a remap.

[isetta]

whilst I agree that overinflating tyres will help reduce fuel consumption I would hope that not everything would go too mad on this as it will reduce grip

[Abbadon]

if its stop start and short journeys it will always be less efficient, due to cold running, etc..Thats what the urban figure is for - and the book figure is always optimistic!

[Hobgoblinpie]

If you're doing short stop-start journeys you're not going to get good fuel economy. When I first got my car the mpg was reading 25 MPG, because the previous owner had used it for travelling around a city. My 1.6 petrol is currently at 37.9 MPG because I mostly use it for long runs down the motorway. 

[mjt]

19 hours ago, isetta said:

whilst I agree that overinflating tyres will help reduce fuel consumption I would hope that not everything would go too mad on this as it will reduce grip

It will also cause the tread to wear faster down the centre.

[FatHead1979]

22 hours ago, gobba said:

its all up to date on services, new cam belt etc, this week i have changed a blown boost pipe, glow plug,, they were no good. main driving is just school runs so it is a lot of stop start but i am not using any heavy acceleration. i will have a look at tyre pressure and i am concidering  a remap.

An engines need to be up to temperature to deliver their most efficient performance (before even considering the type of the journey and driving style etc).  The Lynx engine has a cast iron block so it's virtually indestructible (compared to a soft aluminium block) but it does mean that it takes longer to get up to temperature, especially when the weather turns cold.