Bought a 2010 altima 2.5 with the cvt (yea I know it was a rushed decision lol) And it seems after I fill up the tank full, the gauge will read as such, but then after a very short commute it will drop to near 3/4 then seem to be what id consider more or less accurate for the driving thats been done. I try to granny the thing so imo its not driving habit. computer says ~8L/100km

any idea what is going on here