My fuel bars always seem to be losing 2 bars or so and then after a few minutes it will raise back up to 2 bars. I'm thinking its because since the electronic bars are so accurate that I'm noticing this more than a standard gauges and dials fuel gauge used on most cars. I'm actually getting pretty good mileage on my s2k. Usually I fill her up at about 3 bars left and put $20.00 into her which is like $2.20 a gallon so I know I'm not filling her up all the way. But from that I get about 250 miles? Normal? Its funny because the first 10 bars after the halfway point diminish more quicly than the last 10 before the halfway point. I've been in the 5-10 bar gas area for a longer period than the 10-18 bar. I'm currently at 3 bars and will fill her up after I get out to go to school but no low fuel light yet.

 

Mine fluctuates a bit also, but I've noticed that on all of my cars. My guess is it's due to the fuel sensors detecting varying amounts of fuel as you go up and down hills.

 

Mine really fluctuated one time. It went from about 5 bars down to none, then slowly climb back up to 4 bars. This was all through normal city driving, on level streets with no wild turns. Took it to Honda dealer and they couldn't find anything. Never happened again.

As for the non-linear fuel gauge, I posted about it a long time ago. I usually get about 240 miles before I fuel up, but it seems the first 200 miles will drop the fuel gauge to the half way point, then the remaining 40 miles will use up the second half of the fuel gauge.

 

All depends on the incline, decline, and turn of the car to where the fuel is read. Mine really doesn't start to do it till the last three bars.

 

It's a GUAGE not a fuel exact-o-meter!

 

yeah all depends where the sensor is located, which some people say isnt the best spot. cause on hard turns the car bogs.. i don't know, i'm always too afraid to take turns to hard.. oversteer and breaking loose is a bitch at times on this car.

 

damnit gas is $2.30!! lol went up 10 cents past week. Time for a new gas price thread...

 

The fuel gauge sender is located on the fuel pump assembly in the gas tank. The sender is a typical varying voltage type of deal where a float on the end of a stiff wire goes up and down with the level of the fuel. This wire movement is in line with the longitudinal line of the car (front to rear). I believe the signal is fed into the ECU, that then "averages" out the high "slosh" factor of our gas tank. The reason you see the top half go slower than the bottom half of the gauge is that a full tank has less slosh factor. The ECU will not display instantaneous float levels as this would make the gauge lights go nuts. Therefore, it takes an average. Depending on how you drive and on what sort of inclines you go on, this "averaging" may be skewed from time to time. I'm surprised that so many people find this so remarkable considering what goes on to get you that gauge reading.
Also, if you've ever taken the fuel pump out, when the float is at the bottom of its travel, it would not normally be at or touch the bottom of the fuel tank, so this tells you there is considerable (relatively speaking) gas left when the gauge reads "empty".

 

Mine tend to differ when there are 1-3, they go back and forth all over the place...

 

Mine fluctuates a little. Usually, after filling the tank all but one bar will light up, but 10-20 miles later, all the bars will light up.

I don't rely on the fuel gauge too heavily. I fill up based on mileage, not what the fuel gauge reads.