MPG - does this sound right?
 

Hiya

I put in £20 worth of fuel 2 and reset my mileage counter.

When back to the red as it was prior to puttin in the £20 I checked my count and it was showing 115miles.

I paid £1.119 per litre.

My car is the ZS 120 standard. My MPG seems very low.

And out of that 115 miles around half of it was motorway driving at about 80mph.

Just worked it out and thats 28.9mpg.

Hmmm, parkers suggests my car gives 38mpg.

i get 120 miles to £20 of fuel round town in my 180, if on a run i will get 135

i would expect 300-400 miles to a tankfull on a 1.8

£20 is just under half a tank, so I would get 250ish for a full tank :(

At 80 your pushing it, in a petrol 1.8 your doing well to get that mileage!

if your dropped to 70 on the motorway and refrain from pumping the gas peddle you'll get into the early 35's if you want 38mpg you'll have to drop to 60!

i could be wrong, but the best way to get a accurate reading of your mileage is to fill your tank to the brim do a run and then fill it again.

this is a useful calculator if you need one :)

http://www.torquecars.com/tools/uk-mpg-calculator.php

I did a 700 mile round trip in the wifes 105ZR a couple of weeks ago, and lets just say it was slow, and still expensive compared to my tractor!

I had an interesting though regarding mpg and the apparent fuel consumption of my 180 according to my scan gauge.

I always thought the read out was low due to the scan gauge mph reading being slightly out. I adjusted it the other day using my sat nav but the mpg still seemed low.

I then realised that a US gallon is smaller than a UK gallon!
This much smaller - 1 gallon [UK] = 1.200 949 925 5 gallon [US, liquid]
so I need to multiply the scangauge mpg by 1.2 to get the correct reading.

Huffy is correct, to get an acurate fuel consumption reading you need to brim the tank, any other start point can not be measured that accuratly.

You will definatly get a better fuel consumprion at slightly lower speeds, below 3000 rpm is normally good in a petrol car. Also avoid hard acceleration and braking by planning further ahead.

I get 36mpg in 115+ Derv and Im not cruiseing

The motorway journey to work and home I'm normally at around 3.6-3.8k rpm. Maybe try slowing a little bit for a couple of days....

And if I fill my car to the brim, will the additional weight cause it to get lower mpg. I never fill more than £25 worth of fuel due to weight.