Technical Sh*te MPG. :(
- Thread starter dombooth
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Technical Sh*te MPG. :(
When I try (note 'try') and drive economically I really concentrate on where my throttle is, gear changes don't play a huge part in fuel economy, for example, if I changed up to 5th at 35mph but then had to floor the accelerator to get up a hill I would get much worse consumption as opposed t staying in 4th gear, revving higher but only having say 70% throttle. I always generally shift up and down gears when I know I'll need the same or less throttle in the next gear, changing up and needing to put your foot down harder defeats the point of changing up to save fuel.
Thats just my take on things, generally works, when I do eco runs I get around 4 - 5mpg higher than I do on a normal day.
Thats just my take on things, generally works, when I do eco runs I get around 4 - 5mpg higher than I do on a normal day.
dom the fuel mpg calculators are not very accurate if you don't use them properly.
I doubt any of this is going to make any sence but;
in order to get best results with the mpg make sure your inputting around the same amount of fuel for example
10th feb - 20litres (imput millage)
15th feb - 20litres (imput millage)
If you put the same amount of fuel in when you can from your previous fill up you will have a more accurate result.
another example is where it can go wrong with the calculator
you put 20litres in on 10th feb
then go and put a further 15litres on the 12th for example (like a top up)
if you where to put data into the calulator it wouldn't be accurate and show something around 20-25mpg (depending on the milage) this is because the calc will never actually know how much you already have in the tank and will think you have used all the 20litres from the previous fill.
I doubt any of this is going to make any sence but;
in order to get best results with the mpg make sure your inputting around the same amount of fuel for example
10th feb - 20litres (imput millage)
15th feb - 20litres (imput millage)
If you put the same amount of fuel in when you can from your previous fill up you will have a more accurate result.
another example is where it can go wrong with the calculator
you put 20litres in on 10th feb
then go and put a further 15litres on the 12th for example (like a top up)
if you where to put data into the calulator it wouldn't be accurate and show something around 20-25mpg (depending on the milage) this is because the calc will never actually know how much you already have in the tank and will think you have used all the 20litres from the previous fill.
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ban1111
New member
Mmmm? that all depends on each individual car take the mondeo mk3, with a 6 speed gearbox, it would actually be better in 5th at 56mph on a mondeo speedometer than in 6th. 5th gear 30mph/1000 against sixth gear 35mph/1000 mph..so you are sitting in a sweet spot in the torque and to travel at 74mph you need almost 20% more power than at 56mph to push you through the air.
i do hope these on not trip computer readings as i would love my well sorted 2.2tdci to hit 60mpg at 74mph, but in 4 years have never got it to average that fill up to fill up none build up area travels.....
but you do fill it with the same amount of fuel (in litres) every time? its the only way your going to get a accurate results from the calculator.
with you saying you do start stop all the time thats going to be the killer in mpg unfortionatly
I'm just gonna have to live with it aren't I.
Dom
unfortionatly yes
only thing you can do is like MEP said and also just try and drive generally more smoothy. watching Instant consumpsion can help too. (make sure you still watch the road though )ban1111
New member
Yep that does sound a little daft, and is so. if you drive slowly ie 30 mph or 40 mph in the right gear so not to labour the engine or rev it unduly then thats the best fuel consumption you can ever achieve. if by drive slowly you are changing up and down gears ever 20 seconds,then sure mpg will not be great.. any mpg challenge is based around ave speed of 43mph keeping in the max torque range
driving smoothly anticipating traffic/lights so as not to accelerate harsh and trying not to stop or brake...
Slowing down slowly is no fun though.
Dom
Rubbish, loads of fun annoying everyone following! :slayer:
No, you fill to the same level (ie brimmed and about to dribble out of the tank) not fill with the same number of Litres as thats not going to tell you much.
Surely if you run it dry and then fill with say 20 litres every time it would still be accurate, the calculator doesn't care how many litres your tank can hold so surely it'd just be like having a 20 litre tank?
Personally I never brim my car because if I do and an unexpected payment comes my way I wouldn't be able to afford it (Imma typical poor student)
I had someone use the left hand lane here: http://goo.gl/maps/7ge4k
And go right on me this morning.
Then he pulled into an industrial estate just off the roundabout! What was he hoping to achieve!??!
Dom
:yeahthat:
FIlling the tank to full and running to dry will give you total miles to the tank.
Like my above example, if you where to put 20litres in on the 10th and then another 20litres in a week it will give you an accurate mpg calculation. BUT if you where to just 'top up' in between and put less/more its not going to be an accurate mpg calculation.
the calculators don't know (or care) how much is already in your tank so would think you have already used the previous 20l hence why it would give you a more inaccurate calculation.
the calculators only estimate the mpg reading per data imput, then over a period of 5 (random number) top ups (if the calculator records it) it will give you a overall average from the past fills.
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2.0 diesel 6 speed ghia, yes computer readings. Regular 420 mile journeys always resulted in 60mpg at motorway speeds with 4 adults, wife always managed o get a reading of 61-62:bang:
I'm just gonna have to live with it aren't I.
buy a doblo
To do a manual calculation on MPG you need to fill upto the same point on every fill up, thats the only way you can measure the amount of fuel that has been used on the previous tank full.
Trip computer isn't bothered what you fill with, 5L, 50L, it makes no difference, as it works out MPG on distance, vs fuel used since Trip reset, and driving style. Trip computer is never accurate either tbh, not worth bothering with imo.
ban1111
New member
2.0 diesel 6 speed ghia, yes computer readings. Regular 420 mile journeys always resulted in 60mpg at motorway speeds with 4 adults, wife always managed o get a reading of 61-62:bang:
Right first of all let me say the mondeo tdci is a decent lump and when cruising is indeed a frugal car for its age,but to use a trip computer reading as a fact of
your cars mpg is not a good idea as they over and indeed can also under read at times. the only way to know what your cars real mpg is, is a brim to brim refill/:bang:
2.0 diesel 6 speed ghia, yes computer readings. Regular 420 mile journeys always resulted in 60mpg at motorway speeds with 4 adults, wife always managed o get a reading of 61-62:bang:
Doblo's are too square and van'ish for my liking.
Dom
get an AGP..... 30 mpg in mine currently.... thats not to bad P
On a serious note, its all to do with how quickly you accelerate and brake, there is no point having your foot on the accelerator for 15 seconds before you have to brake.
Little changes like that will make a big difference in stop start driving, and also how quickly you accelerate determines fuel use.
hilariously, it has been tested that full acc to 2,000 rpm and change can increase mpg
POn a serious note, its all to do with how quickly you accelerate and brake, there is no point having your foot on the accelerator for 15 seconds before you have to brake.
Little changes like that will make a big difference in stop start driving, and also how quickly you accelerate determines fuel use.
hilariously, it has been tested that full acc to 2,000 rpm and change can increase mpg
get an AGP..... 30 mpg in mine currently.... thats not to bad
On a serious note, its all to do with how quickly you accelerate and brake, there is no point having your foot on the accelerator for 15 seconds before you have to brake.
Little changes like that will make a big difference in stop start driving, and also how quickly you accelerate determines fuel use.
hilariously, it has been tested that full acc to 2,000 rpm and change can increase mpg
I would love an AGP but don't think it'll go up my drive.
Yeah, I don't accelerate/brake that quickly but I don't like messing around.
I'd be forever changing gear and never get anywhere doing that.
Dom
I haven't touched/used/looked/reset trip computer. I work out mpg via millage > per gallon per fill up then my app averages it out over the previous data inputs
