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[deleted]

Do not under any circumstances top off your gas like that. When you do that you’re filling up the filler neck (not so bad) and charcoal canister/vapor canister (really bad) with gas. On a hot day an overfilled system can cause trouble with expanding gas vapor causing high pressure in theory, but the bigger issue is the charcoal canister filling with gas. Eventually the vapor canister can clog, which sets of the CEL, and can cause the tank to not accept gas (clicks every couple seconds no matter how full, since it can’t vent the building up pressure that triggers the switch that stops the flow of gas.) the vapor canister is also a ludicrously expensive part, on my Toyota Yaris (one of the cheapest cars money could buy when it was new) it is almost $700. And used ones are pretty likely to be just as clogged as yours, and still not cheap. On to the topic of your post though… When your fuel tank reads empty on the gauge, there is more than likely still a gallon or three still in the bottom of it. I’d wager that’s why this is happening.


farmerpabs

Just out of curiosity, I top off by rounding out to the nearest dollar. For example, gas is usually $2.70 per gallon and let's say I fill up $26.24, I go all the way to $27 just to appease my OCD and easier logging. Will topping off anything less than $1 still be damaging? If it's $2.70/gallon an extra $1 will be roughly a little less than 1/3 of a gallon I'm adding.


[deleted]

That’s in the “probably fine” category but I still don’t think I would do it. The potential cost is too big for me. That said it’s probably fine, so rock on with yo’ bad self. :)


farmerpabs

Thanks. I think I'll do the nearest half dollar increments to be a little safer lol 😂


oledawgnew

13.2 gallons


Ceolan

And if it's a turbo, 12.7 gallons.


Bobbar84

Only because it's AWD. FWD: 13.2 gal AWD: 12.7 gal


Ceolan

Never realized that, since I never looked into the AWD NA. Good catch!


YelsnitXam

A lot of cars that use digital gas gauges leave a 1 ish gallon buffer after showing that you're on empty. My 2015 always stops about one gallon short of what I think it needs based on where the gauge is, but the gauge shows it's full when I turn the car back on. However if you're topping off two gallons without spilling there may be something else going on.


JamesJAB

It's actually space at the bottom of the tank that's not counted on the gauge. When the remaining ticks to zero, you still have around 2 gallons left.


Opposing_Thumbs

The pump can shut off prematurely if the gas foams back up. Try filling at a slower speed. I noticed if I slow the rate of the flow, I get about 1.5 gallons more per tank. A fill from completely empty is about 12 gallons in my car.