mpg need help

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gaszman
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Post Mon Dec 24, 2012 9:57 am

ok i did 254 miles
filled up only got 44 ltrs in tank 55l tank
did 26.35 miles per gallon
how many more miles would she go in 11 ltrs cant find it

any brainy people here
so i can calculate the miles per gallen prop thats all

dodgy gauge
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Grrrmachine
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Post Mon Dec 24, 2012 10:09 am

11 litres is presuming you can get every last drop out of the tank, which isn't going to happen. But to talk you through the maths:

Divide your distance by the fuel you used: 254 / 44 = 5.7
That means every litre will get you 5.7 miles.
Since you've got 11 litres left, multiply 5.7 x 11 = 63.5
So you'd get a further 63.5 miles on 11 litres.

To calculate miles per gallon, multiply your miles-per-litre (5.7) by 4.54, which in this case equals 25.9 mpg. Dunno how you calculated you did 26.35mpg, unless that's just what your OBC told you.
Gortour
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Post Mon Dec 24, 2012 10:11 am

A gallon is 4.54609 litres.

11 litres is roughly 2.4 gallons.

2.4 gallons times 26 is about 62 miles Dave.
Currently slumming it in an E46 Touring
gaszman
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Post Mon Dec 24, 2012 10:13 am

did it on line 254 miles on 44 ltrs = 26.34 as i have a 55 ltr tank another 63 miles is a bout right when the red light comes on dont we have 50 miles left
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Grrrmachine
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Post Mon Dec 24, 2012 10:20 am

The low level light comes on when you've got 8 litres left. It has no idea what mpg you're doing so has no idea whether that 50 miles or 100. But at your current mpg, it'll be 45.6 miles.

You really shouldn't run the engine with that little fuel in it though. You'll be sucking up all the dregs in the tank and trying to pump it into the engine which will clog your filters, gum up your injectors and make your engine run like sh!t.
gaszman
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Post Mon Dec 24, 2012 10:27 am

yes mate cheers sounds about right
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gaszman
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Post Mon Dec 24, 2012 10:28 am

271 before the light comes on sweet better than 200
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