mpg calculations

hiya guys.

was wondering if you would be so kind to help me please.

before i fit the synergy, egr bypass and crankcase bmw kit i would like to accerately work out my mpg.

am i able to do it without filling the tank to the brim please, as it will take a while and cost me about £80.00 per fill up

sorry to be so dense but wish to get an accurate way so i can see what my mpg is before and after

if i did have to fill it to the brim when do i take the reading, when the low fuel light comes on, but then how much fuel is left in the tank when the light comes on.

thanks so much and sorry for being so dense :doh:

all the best

gary

I believe filling to the brim is the most accurate way do do it.

However, the stated tank capacity is 59litre. You can figure out how much there is after the light comes on if you fill the tank again. But probably there are about 5 litres left in tank.

I usually calculate mpg (or l/100kms in my case) by filling up and reseting the trip. Then I fill up again and figure out how many kms with the diesel I spent before filling up.

Anyway, it seems that running low on fuel isn't very good for the fuel system (crap from the tank being sucked out)

Just brim it once and then run a few miles until you fill it up again (100 miles p. ex.). It will be cheaper each time and more accurate than waiting for the light to come on

Cheers

You have to brim the tank, relying on the light will not give you an accurate reading. As already stated, why not fill it once and then refill it after 100-miles and then again after another 100?
Personally I always brim all of my vehicles, why keep putting £20 in and then have to go back a few days later to put another £20 in? Ok it may cost £60-£70 (even the 90 took £60 this weekend) but it means it lasts longer. By always brimming the tank I am also able to do a MPG calculation every time I fill up, I have done this for years and can accuratly monitor what each vehicle is getting.

I agree, I fill it up till it stops three times, reset the trip and drive until i've used about 3/4 of the tank, then fill it up again and record the mileage that i've done. Then it's a simple calculation of miles divided by the number of gallons used (litres x 4.45). A few of these and take the average is probably a good bet. Mine previously came out to about 25, it's now about 30 after a clean of the breather tube. Having recently mondo'd it, i'm hoping it will go up to about 35.

thanks guys, i will do that,

may i ask what is the average mileage you get from a tank full please.

so as you say i can brim the tank then do about 100 miles then refill and see how many litres go back in.

im sorry to be so dense about this

gary

I don't know how many miles from a tank but I know my wife's manual TD4 does about 36MPG when commuting, she still hasn't done a long journey to see what it gets on the open road.
It doesn't matter how many miles you cover before refilling just as long as you fill to the same level every time. When you have done this you work out the number of gallons used (divide the litres by 4.54) and divide this into the number of miles covered.

getting 27mpg out of my td4 auto at the mo, been that way for about 3 months now

thanks guys,

will fill up tommorow will work out the mpg before any mods, then retake the mpg with the crankcase fitted, then the egr then the synergy.

the other thing if i may ask, is it just as easy to put in shell advanced instead of putting millers or redex in, just a thought

i know i need to get out more

all the best

gary

My TD4 auto is doing an average of 33mpg (that's 8,5l/100) - no mods 80k on the clock.

Just divide the litres you put in by the kms you did and multiply by 100. To calculate mpg I use
Fuel Efficiency Conversion - Online Unit Converter

Hiya, not too sure what I am likely to get out of a tank to be honest, though probably about 250 motorway miles is roughly close. 27mpg doesn't sound great, Optimus. Running a bit rich? I wonder whether a faulty VCU reduces mpg as the wind-up must take some power.

On the question of using super petrol, not too sure but i tend to steer clear and use normal unleaded and redex as i know exactly what is in that.
You ideally want to use quite a lot of the tank to reduce the difference that any topping-up variation includes, and do it a few times to get an average reading.

thanks about the info on the redex, i looked at a bottle the other day and the instructions arnt very clear it looks as though you pour the entire bottle in, it also has a line on the bottle cant make head or tales of it.

plus i also found this online

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

all the best

gary

think you can work it out without the need to fill your tank

Fuel Calculators » Fuel-Economy.co.uk

this helped me get an idea on fuel usage on my freebie

mine guzzles alot of juice when your heavy on your right foot, I suppose it doesnt help having the synergy on setting 10 ! lol

An Auto will always consume more fuel,
when I bought my TD4 Auto, I religously checked the mileage over a period of 2 years, tank to tankful.

My daily 20 mile round trip to work which is best described as urban - doesn't have heavy traffic, but includes a lot of roundabouts and traffic lights - so the auto does a lot of shifting.

This gave a fairly steady figure of 28mpg in Winter and 30mpg in Summer


The best I ever got was by keeping to a strict 60mph on a straight motorway run from Kent to Yorkshire and back.
I kept as steady a speed and light foot as possible so the auto stayed locked up in top gear, real boring and tiring to concentrate, but...

....this gave a phenominal 45mpg

I've done this twice, and got approx the same both times

What mileage do you get from a full tank on your td4 auto ??
I have a 53 plate td4 auto filled up wi just under £80 and covered appx 330 miles and needle is nearly on the red now .

Cheers Drew

Approx 350 to 370 miles

Ok ty mark it must be about right then .

Optimus Prime said:

getting 27mpg out of my td4 auto at the mo, been that way for about 3 months now

Click to expand...

I'm about the same during the winter months as you Opti. Always like this & performance isn't as sharp, as soon as the warm weather comes, both performance & economy improve - probably cause fuel flows a lot better. Been the same with every diesel car I've ever owned. Even thought about getting a wrap round fuel filter heater pad but I've only ever seen them available in the USA & I'm not paying those greedy customs B****** anything so I'll just leave things as they are.

yea, im getting 200 miles on 40 quid with the synergy set on the highest (10)

not bad i think

can i ask what the synergy is plz guys???am lost lol

a little box that plugs into your TD4 engine and adds extra grunt and BHP / Speed

well worth getting one !

ask anyone, they will all agree

makes the TD4 a super charged 4x4 ! lol