So I notice something screwy with my Mileage Estimation.

The 2015 Fit has a 10.6 Gal tank. Well the other day I drove down to 1% and need to fill my gas tank. After filling my tank, I only filled up 8.6 Gallons. After I filled up it said I my range is 300 miles. It seems like the range reading is off. Has anyone else noticed this?

 

Without getting too techy with the physics of gas laws, you need room for the liquid fuel to expand into a gasous state. If you filled it all the way up to its max capacity without the room to expand the pressure inside the tank when sealed can cause issues.

For long road trips I take the gas pump nozzle slightly out of the filler neck so that it does not sense the pressure as fast. You squeeze about a half gallon more in there before it's simply too full to accept any more fuel

 

The fuel gauge and fuel flow measurement in the Fit are "consumer grade" and therefore inherently inaccurate. Honda's software is conservative so the car will not likely tell you that you can go farther than you can. Even though you were down to "1%" there was likely still a gallon of fuel left.

In my experience most tanks hold a bit more than their advertised capacity. You might have to fill the last bit slowly.

 

Heres a good thread on the issue :

https://www.fitfreak.net/forums/3rd-...uel-gauge.html

 

That's rather misleading, at best. Gasoline in the tank remains liquid so long as it's in the tank. You do need a little space for expansion of the liquid with temperature, as its density (and hence volume) does change some, but that's not what is accounting for the couple of gallons of "missing" fuel. That would only become a problem when there is no head space left in the fuel tank. Expansion into a gaseous state (which is just evaporation) is more a matter of the pressure in the tank and the vapor pressure of gasoline, and has nothing to do with how much head space there is in the tank.

The "problem" here is just the programming of the range indicator thingy, which is very conservative, presumably to prevent people from possibly running out of fuel. It sounds like one could go another fifty or more miles after it says you've run out of gas before actually running out of gas—not that I recommend cutting things unnecessarily close, of course.

 

Kind of false advertisement. On my 09 Fit, the gauge was great when it said it was close to E. It is nice to know, I was not in the red about getting somewhere to get gas.

 

I am happy if I can get around 330 miles on one tank.

 

A ScanGauge or an UltraGauge is easy to calibrate and can display your actual fuel remaining, letting you make your own decisions about when to fuel up. You can also see actual coolant temperature, actual mpg...

Now that summer's here I'm enjoying the longer tanks. I hate stopping for gas!

 

Gauge is just doing its job gauging.
It's not a precision metering device.

 

I like to think of it as a reserve tank, although two gallons is a bit excessive. I've definitely run for 10+ miles with 0 range and nothing on the gas reading. Would be nice if one of those gallons was read on the gas gauge.