how many MPG am i really getting?
Posted by: AL4N on 16 January 2005
with some of the greatest minds on the www at my finger tips i was wondering how to work out my MPG on a recent trip to London and back.i covered 530 miles and it took £41 to fill up at 84p a litre it took 49 litre's,so how's it worked out?any taker's?
Posted on: 16 January 2005 by J.N.
I make it 49.357 mpg.
John.
Litres to gallons - multiply by 0.22
Gallons to litres - multiply by 4.545
Posted on: 16 January 2005 by Steve2701
Taken..
When I was finally allowed to log in.......
49 litres = 10.7784 Gallons (UK) acording to ask jeeves.
So my calculator says 49.1724 miles per gallon... blimey dare I ask if this was petrol driven?
Posted on: 16 January 2005 by AL4N
it is a golf 2.0D,that said,i didn't go over 80MPH either way.
Posted on: 17 January 2005 by Don Atkinson
Call it 50mpg.
Why?
EVERYTHING you have quoted is probably an approximation, plus the same journey tomorrow will swallow a slightly different amount of measured fuel.
Just don't push that extra mile once the "low fuel" warning light comes on....
Cheers
Don
Posted on: 17 January 2005 by Rana Ali
Don's right. Last automotive OEM project I worked on, a few of our pre-production durability cars were running out of fuel when their computers said they still had a few km left. A quick investigation showed that manufacturing tolerances in fuel tank dimensions and injector flow could easily throw the "mileage left" algorithm out of kilter. Rather than set everything to worst case (in which case 99.9% of customers would see a fuel consumption worse than was really occuring), the simple solution was to extinguish the calculated information from the display as soon as the reserve level was hit (to something like "Refuel Now" - can't remember the actual wording).
Posted on: 18 January 2005 by Bosh
Of course the MPG also relies on an accurate mileometer which most are not
Posted on: 18 January 2005 by 7V
quote:
Originally posted by Bosh:
Of course the MPG also relies on an accurate mileometer which most are not
Tim de Paravicini (of all people) once told me that speedometers were made about 8% optimistic because of some European legislation.
Does this also apply to mileometers?
Steve M
Posted on: 18 January 2005 by Brian OReilly
Speedometers +7%/-0% for obvious reasons.
Mileometers +/-4%
Posted on: 18 January 2005 by 7V
So here we're talking of between 47mpg and 51mpg.
Steve M
Posted on: 18 January 2005 by JRHardee
Was your tank just as full when you started as it was after you filled it up? If not, you can't calculate anything to any degree of accuracy.
Posted on: 18 January 2005 by AL4N
i fill it up as much as possible each and every time,i let it settle for a few seconds and repeat a couple of times,( a pain in the arse if you are waiting behind me) so it's as close to the same each time,any-hoo,what could the difference be,a couple of cups full,?and on a 530 mile trip that won't make too much difference i wouldn't have thought.
Posted on: 18 January 2005 by BigH47
You should easily get very high '40s to mid '50s or more from a VW diesel. My 1.8 8v GTI petrol does low '40s on long motorway journeys( at the speed limit of course
). It actually does better mpg at 80 than 70 mph.
Howard
Posted on: 27 January 2005 by Martin Payne
quote:
Originally posted by AL4N:
i fill it up as much as possible each and every time,i let it settle for a few seconds and repeat a couple of times
Hmm, careful there!
Do that on a cold day when very close to home.
If the next day is very warm, and the tank still brim-full, then the liquid will expand so that it is bigger than the tank.
Expect a leak of diesel.
cheers, Martin
