tank fill up issue: 2013 Civic EX

[Abedin]

Hi guys,

I recently bought a 2013 Honda civic EX. It has 66000 km milage.
I noticed that whenever I fill up the tank, my odometer has always underestimated the range with a full tank. Let me explain what I mean. Given the volume of the tank is 50 liters, when I fill it up to the point where the gas pump clicks and turns off, indicating that the tank is full, the odometer displays that I can travel only 500 km, with an average fuel consumption of 7.5 liters/100 km. This does not make sense to me. A simple math shows that if the tank was full i.e you have 50 liters of gas, then you should be able to travel 660km roughly (of course given that you maintain a gas consumption of 7.5 l/100km). For some reason, the range calculation by the computer is well underestimated.

Here is what I've noticed. From the first click indicating the tank is full, I kept going and pouring gas into the tank and it actually took additional 8.5 liters until you actually spill a little bit a fuel (or completely full). Is that normal???? That means that when I was filling my tank before and trusting the click that the tank was full, there was actually only 50 liters - 8.5 liters = 41.5 liters in the tank. Now if we consider that there was really 41.5 liters, then the range should be 550 km (roughly), which is more consistent with 500 km, compared to 660 km.
Do you guys think this is normal, or should I take the car to the dealership and report the problem.

Your help will be very much appreciated.

 

[Abedin]

@boofoo, I will check the owner's manual but to answer your last question. Yes, when the pump turns off after the click the gas gauge shows that the tank is completely full. Regardless, I am able to put additional 8.5 liters (if I ignore the click and force fill it).

 

[HeX]

Also keep in mind that every legal production car that I know of will not read red only when its completely empty, digital or analog, but down to a very low amount. The "empty" warning is more of a "hey, get gas now. you waited too long" warning. The remaining reserve amount will vary by car, so don't overthink it.

 

[20Civic12]

My 2012 Civic does the same thing. I don't know how it compares to yours but here in US were gallons and when I fill up my car the pump kicks off early and I'm able to usually keep squeezing and get another gallon to gallon and half in there. This makes a huge difference for me because I commute a 100 miles a day. It usually means having to refill a day earlier then I'd like if I don't completely fill it. What I'm told is that the EVAP canister needs to be changed and this issue of not filling up all the way, will go away.

 

[20Civic12]

Ok, well hadn't heard that you'd damage it, but what do you got to support that? Not doubting you but I like the extra gallon but I believe mine is definitely bad or damaged. But if that is what is truly causing it that would be good to know. I had this same issue on a different vehicle and was told that replacing the canister would fix the issue.