Hey guys - my 2010 Honda Civic LX has a 13 gallon tank, and get 36 (sticker - holds true) MPG on the highway, where I mainly drive it, and about 26 in town. So I get about 400 miles on a tank of gas - not bad.

My question concerns the gas guage. When I top off the tank, the gas gauge will show full for about 200 miles, then it will start to fall off, and it drops like a rock when the gauge "shows" half-empty.

Is this normal? I'm under the impression (a correct one) that the gas gauge should accurately show the amount of gas left, not just when it gets less than 200 miles left.

Everything is electronic, of course, so should I just wait a few weeks and see if it sorts itself out or what should I do? And there's no danger of me running out of gas anything, I pay good attention to it, I'm just concerned.

 

Worldwide, most gas gauges are at best moderately accurate. Many have quirks, where they do oddball things. You have to learn what yours usually does.
The best bet is, don't go by the gauge. Go by mileage. Pick out your favorite and fill up every time when you get to that mileage.
Do not run the tank too low. Keep at least a third and never less than a quarter of a tank in there.
Do not run it out of gas.
Fuel injected cars run on pressurized fuel, which pressure comes from the fuel pump. Air compresses. The more air in the tank and the more the pump has to pump to get the pressure up.
As it gets lower, it can run poor.
Always get it filled. That way you don't waste extra gas going to get gas several times.
dc