cu2 fuel usage question.

[aussiebuddha]

Does anyone know how the fuel consumption gauge works?
I know it's an average, but when it for example says 10/100km, does it mean it's using that now or it's the average usage since I did a reset?

these fuel prices are concerning me :-/

[mikey72]

if it's the real time one it tells you what you are currently using.

[aussiebuddha]

aw bugger.
how do you calculate the fuel usage without going into manual km per tank?
I always hated doing that because I never use a full tank, and hate refueling with yellow light as it might not be on the "cheap" day.

[mikey72]

just reset your trip metre when you fill up. when you fill up the next time record the amount of kilometres you have travelled and the amount of litres of petrol it takes.

and then just enter them into this site.

http://motormouth.com.au/myvehicle/consumptioncalculator.aspx

[aussiebuddha]

aw bugger.
how do you calculate the fuel usage without going into manual km per tank?
I always hated doing that because I never use a full tank, and hate refueling with yellow light as it might not be on the "cheap" day.

thanks mate, sounds good but can you get the litres used from the dash? i dont think i've seen it though i haven't looked carefully.

[mikey72]

never trust a fuel gauge. :)

[opilot87]

thanks mate, sounds good but can you get the litres used from the dash? i dont think i've seen it though i haven't looked carefully.

Yes you can, I don't have a CU2, but in (as far as I know) all trip computers will give you both an instantaneous and average fuel consumption. Instantaneous is at the minute, at the current load and speed fuel consumption, so this jumps all over the place as you accelerate etc. The average fuel consumption is the average consumption since it was last reset. So if you reset it every time you fill up, reset it!

Ollie

[CU2 Euro 09]

yeah, the CU2 has real time and average fuel consumption displays in the trip computer.

[chunsa]

I found that the average fuel consumption is usually off by 0.3-0.5L/100km. e.g. if it says 10.5L/100km, you are really using about 10.8-11L/100km (calculations are based of using how much is filled at the petrol station and how much was travelled with the car's trip meter.)

[Type R Positive]

The bar graph screen is real time obviously, and the other number reading fuel consumption screen is an average.

[aussiebuddha]

yup, bar graph is definitely real time.
The average one however, I'm not sure whether it's averaging in the last few minutes, or since the trip counter was reset to 0
but if it's like you guys say, since it was reset to 0, it's great! no calculations needed

[buddah51au]

The Bar graph is real time which I never take any notice of. As well as that the trip computer gives you 2 displays, 1 can be set to automatically reset every time you fill the tank, another gives you long a long term average, but only as high as 9,999kms then it reverts to 0. As chunsa said, the display is 0.3 to 0.4 below your true average.