Be careful with fuel gauge, it can be misleading and that could cause
you to misunderstand the true Mileage. I have been watching my MB
and Infiniti fuel gauges for over two years now, they both seemed to
have similar effect. A certain section of your fuel gauge could drop
too faster, and another section will drop slowly. Make sure you put
a note to remind yourself to compensate for the difference, and make
sure you are familiar with its behavior. Change the section by
testing your car at different needle position.
Tiger is absolutely right on this one. Gas gauges are not accurate
enough to use for mileage. The only points in the travel that they
have to be correct are at full and empty. And actually, now that I
think about it, that's not even a true statement. They have to err on
the safe side. Basically your gas guage has to read full when the tank
is less than full. This prevents people from trying to overfill their
tanks because they think it is not yet full. Unfortunately there are
dampers in the circuit that cause the needle to take a while to get up
there, so this rule is kind of moot, but then again most people don't
fill their tanks like that anyways. The other point it has to be
'correct' is at empty. The gauge has to read empty before you are
actually empty. If it says you have 1/8 tank and you run out of gas,
that is bad. A few automakers--Mercedes and BMW are among them--have
tried to put the remaining marking roughly where they should be. That
is why the distance between 1/4 and empty is not the same as between
1/4 and 1/2, or even between 1/2 and 3/4. However, a point halfway
between 1/4 and 1/2 on the gauge is most likely closer to one than the
other. So trying to determine the amount of fuel used byusing a gas
gauge is pretty difficult. Especially if you are only talking a small
amount under a gallon in a car that can hold 15 to 20 gallons.
In general fuel gauges are precise if you are parked in the same
spot(same orientation) and given enough time to settle, but definitely
not accurate by any stretch of the imagination.
My method was to use the computer. I reset it at the beginning of the
distance and then it ended up with average MPG for the period. Not sure
how accurate it is, but steady, slow driving without any sudden
accelerations and braking yields decent MPG.
I noted it too with a great relief - provided you or on flat it matches
computer indication as well the observed growing distance - 3/4 = 100
miles done, 1/2 = 200, 1/4 = 300 and empty tank = 400 miles when driving
in similar conditions. I also like that the reserve light goes off
exactly when the needle moves over the light.
All unthinkable with other cars.
highway only, 25 miles, average 29.5MPG. AFAIK my model of the car does
not show the instant MPG. And remainings of higher octane in the tank
were negligible since I did my experiment way long after the almost 100%
Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here.
All logos and trade names are the property of their respective owners.