This is my best guess as to which forum to use for this question -- sorry if I missed a better choice.

I've been driving Civics for 20+ years and have never known just how much accessible gas tends to be left at the point when the low fuel indicator comes up. I always hustle off to essentially the nearest gas station just to be on the safe side (like I did tonight ), but I've always wondered whether it's really necessary to treat that light as a Right Now kind of thing or whether one might have a leisurely 1/2 gallon or whatever to draw from.

Does anyone know?

 

My tank has ~2 gallons when the light first begins to flicker on. If it's on steady, then you may have 1 gallon or less.

 

Well when it comes on, fill up your tank. Take the capacity of the tank and subtract the amount you just put in it. That is how much you had left basically.

 

I'm assuming there's some amount of fuel that you just can't use, that the engine will sputter out not because there's no drop of fuel left anywhere in the system, but because the fuel level has dropped below that which can successfully be delivered to the engine. For example, does the tank really get drained bone-dry, or is there a bit in the bottom that you never really get? Is there anywhere else that bits of it might pool when the fuel line is no longer full? It's the amount of inaccessible gas that I'm really wondering about.

When my light comes on, I generally put about 11.4 gallons into what is purported to be a 11.9 gallon tank (if I remember correctly). So there's technically a half gallon left, but can I really use all of it, or most of it, or hardly any of it?

That's my real question. Sorry I didn't ask it better the first time.