fuel consumption lower than normal...why??

[hovis007]

hi
i have a signum 1.9cdti 150 and i 05reg...i have had it for about 2 and a half years and i have always been very pleased with the fuel consumption...usually getting around 40mpg and more closer to 50mpg on a long run...but just lately i seem to be getting about 10mpg less...there is no loss in power but i am baffled with this.....anyone had a similar experience as to a quick fix....i just cant bear to see my computer readout showing 30mpg or even less.....what can it be??

[bigmac]

Service may help but all so the price of fuel has risen so you may get less for your money

[hovis007]

just recently had oil and filter change and also new discs and pads on the front....i have wondered about breaks sticking a bit but surely if they did stick even slightly they would be glowing and smelling burnt...but they are not

[bigmac]

Diesel filter ? air filter ?

[Ademusic]

Tyre pressures? Changed the garage you buy from? If you get stuck in traffic after filling up, your mpg will drop lower than it would if you filled up and went on a long run with no traffic etc, if that makes sense

[hovis007]

must admit to not having air and diesel filters this time coz they were done about 8,ooo miles previous.....but this drop of 10mpg seems quite sudden

[the-wizard]

try some injector cleaner, have you had the manifold changed ?, a GOOD service cleaning the egr and boost sensor aswell wont do any harm!. i noticed a drop in mpg when my manifold was shot!.

[m8internet]

What method are uisng to calculate the average MPG?

I tend to watch the amount of miles per 7 litres (roughly each mark on the fuel gauge)
I get between 30 and 50 miles, or equivalent to 240 to 400 miles per tank
When you consider that, that is some variation on a small amount of fuel
However, in the longer term the average MPG is between 32 and 33 mpg

[mickydoos]

As said before, check your tyre pressures. Mine were 4 psi too low and was costing me 3 or 4 mpg. I cant see why usless you've become majorly heavy footed as of late?

Easy way to calculate your mpg:

1)Fill your car to the top. As much fuel as your can get in it.

2)Reset the trip mileometer (whatever you wanna call it)

3)Upon your next fill up. Take note of the amount of fuel you put in it.

4)Then convert your litres of fuel to UK gallons (US Gallons are smaller)

5)Divide miles completed by fuel used and presto! An accurate fuel economy reading.



Either that or get an app for your phone which does it for you (like I did).

HTH :P

[Celes]

What method are uisng to calculate the average MPG?

I tend to watch the amount of miles per 7 litres (roughly each mark on the fuel gauge)
I get between 30 and 50 miles, or equivalent to 240 to 400 miles per tank
When you consider that, that is some variation on a small amount of fuel
However, in the longer term the average MPG is between 32 and 33 mpg

Sorry mate but how do you drive your car to get such bad mpg?