petrol consumption

[dothawkes31]

if i put £30 of unleaded in the car last friday and on the reciept it says 27.55 L @ 108.9p, and I have done 130 miles now, how many mpg is my car doing and how many miles left with that petrol should i have left in theory?

[dothawkes31]

oh i hadn't run out there was some left and i've just put another 15 quid in

[factor-fiction]

panic button- I thought she meant how much petrol had she got left (which would invalidate the assumption the needle had returned to its starting position)- but I think Dot means how much should she have left IN THEORY if the car had achieved its manufacturer's MPG rate rather than her back of the envelope actual MPG rate. Basically i think the data is meaningless for all the reasons given

[factor-fiction]

Now with this new info I think dot is winding us up. I'm getting out of this thread

[Panic Button]

My head hurts

[cazzz1975]

when I owned a 306 1.8 in perfect working order it only ever did about 32mpg max

[dothawkes31]

ahh right, so i have still quite alot of the 30 worth left as my car does more mpg than that

[B Rubble]

The way I use to do it you could try this…

1. Fill the tank up to the click.
2. Zero the tip meter.
3. Drive as you normally would until your next fill up.
4. Now fill the tank up to the click again.
5. When you pay get a receipt and note the mileage you have done
6. Then do the following calculation.
7. Number of Gallons of Fuel = No of litres of fuel ÷ 4.5461
8. MPG = Miles Recorded ÷ Number of Gallons of Fuel

e.g.
No of litres = 35
Miles covered = 250

35 ÷ 4.5461 = 7.699
250 ÷ 7.699 = 32.472 mpg

Do this a few times keeping a note of your mpg then you can assess the average.

[carlton23]

It all depends on how heavy your foot is on the gas peddle,and heavy braking and running heaters, and other electrical gadgets in modern cars, all make for using fuel, also carrying heavy objects unnecessarily all add up to less economy in cars.