Hello friends ,
today i looked on my instant fuel economy (Live Fuel consumption) and i saw thet it'* not consistent , it jump from 10L/100KM to 27L/100KM . and i no touch anything . it'* happend specialy in low speeds .

why is that ?
how it calculate the fuel consumption ?
maybe is related to my problem (the car not keep the speed right , like other buick'* that i had)
my mileage very poor too , maybe some sensor are not working well ?

thanks

its normal, and as far as your issues, please stick to one thread, i had a question there and posting multiple threads just confuses things.

The instant is all over the place unless you are are on the highway at a consistent speed.
The car in town is variable as to how much throttle and reads 0 not moving, at idle.
One thing I will say is that the fuel used on mine is very accurate.
I can drive around town or highway and know how much fuel it needs, that is handy!

As mentioned, the "instant" reading will almost always jump around quite a bit. Digital gauges are hard to read variations too, if there were such thing as an analog (i.e. a fluctuating needle) gauge for instant MPG'*, you'd see the needle predictably drop when accelerating/braking, and rise when cruising.

"Average" mpg reading should stay mostly consistent. Mine sits steadily at about 25.5 for about a 60/40 mix of highway/city which absolutely thrills me for a larger vehicle (by today'* standards anyway) that rides so comfortably.