Topping-Off

[SilverBullet]

Usually, when I fill the car with gas I top it off slightly to get to a more even price or squeeze a little more gasoline into the tank. Most pumps advise you not to top off your car so I was wondering if anybody knew why? Is there any harm to the car's fuel system by topping off?

[Keyan]

Because it ends up over filling the fuel tank and the extra evaporates....

[05xd]

If excess fuel comes back up to the top of the filler neck,it can go back down into the charcoal canister thru the vent hose and cause the canister close valve and purge valve to stick open or closed and cause a CEL

[SilverBullet]

i guess from now on I will let the pump decide when enough is enough....

[joshuajd]

Actually if you overfill your tank you are ripping yourself off. There is a fume recovery system that is required to take fumes in as it dispenses gas. If the gas gets over a certain point on the nozzle it starts sucking gas in. That is how it shuts off when over filling.

[SilverBullet]

well, I don't usually let the gas spew out into the filler inlet neck, I only go about 25 cents over which is enough to give me a few more "miles till empty". I don't think this means I'm not getting the quarter of gas...Nevertheless, topping off is bad and it serves no real purpose.

[4mynikka]

I never top off... when it's full it's full.

[CTele02]

25 cents over

Just for the hell of it:
hmmm... at $2.40 a gallon:
0$.25/$2.40 = 0.10417 so thats 10.417% of a gallon...
now at say 30mpg:
.10417 * 30miles = 3.125miles...
Thats a very few more miles... that you'll probably never get since it would just evaporate...
Plus even when your Oil Gauge is on E... you have about 1-2 (safety) gallons left... and by then you should be heading on your way to a gas station...

[robs02elantra]

Just for the hell of it:
hmmm... at $2.40 a gallon:
0$.25/$2.40 = 0.10417 so thats 10.417% of a gallon...
now at say 30mpg:
.10417 * 30miles = 3.125miles...
Thats a very few more miles... that you'll probably never get since it would just evaporate...
Plus even when your Oil Gauge is on E... you have about 1-2 (safety) gallons left... and by then you should be heading on your way to a gas station...

I don't know how many gallons of oil you put in your car, in the plural...but just to bust you up about something for no reason, and for the hell of it, you mean Gas Gauge, right?

[CTele02]

eh you know we all REFER to gasoline and petroleum as OIL... sure in its crude form but whatever... just some slang... my bad.

[robs02elantra]

yeah, sorry. You just never know who's reading this stuff. Off topic, I talked with a girl tonight who I was going to change her spare tire (she got a flat this evening before I caught up with her) from her front left wheel to her rear wheel because it's better to keep the driving wheels the same and not have such a bad difference. Especially in the snow. And she was like "well, how long will it take...no, I can't wait that long, you would have to give me an alignment and then put the wheels back on and..." even after we told her that an alignment isn't necessary when you change wheels, she still said, "It's ok, I'm only driving to Fergus tomorrow, it will be ok." Fergus is an hour and a half drive.

Anyway, all that to say, some people can take it literally...and I don't really want anyone around here to go and fill up with just oil. Haha, bad scene

[importdriver05]

well i learned the hard way bout topping off, when i first bought my car i traveled alot so therefore i topped it off, and friday my cel came on b/c of this, so monday i have to take it the dealer to get fixed, hope its a warranty thing b/c i figure its gonna be expensive.

[quickfingerz]

First of all you should use a 5% rebate gas card.

But that does make me reconsider how I do mine because I will round my amount to the nearest odd tenth (.10, .30, .70, .90) just to get an extra penny rebate since I may be losing it all to evaporation... just for a penny.

[1SweetV6]

Well from reading this it sounds like u shouldn't top off. Thing is my wife & I have always topped off. First few tanks maybe not but after 3,000 miles on the car we started to. Normally I would go 1 to 2 gallon over the stop. Since we found we could go an extra 50 to 60 miles. she does 100 miles a day. So far we have done this for about 10,000 miles.

[southpawboston]

well i learned the hard way bout topping off, when i first bought my car i traveled alot so therefore i topped it off, and friday my cel came on b/c of this, so monday i have to take it the dealer to get fixed, hope its a warranty thing b/c i figure its gonna be expensive.

it should be warranted, but also it may be something as simple as the gas cap not being tightened enough... that's a common cause for a CEL.

[hyunelan2]

There is a reason gas stations say "do not top off tank." Signs are your friends - you should read and obey. It's not like you NEED that extra gallon in there - unless you are running the car down to ZERO fuel everytime, you won't even know the difference (and if you're running the car to zero fuel, there are a few people here that will probably yell at you for that).

[TwiZ]

If excess fuel comes back up to the top of the filler neck,it can go back down into the charcoal canister thru the vent hose and cause the canister close valve and purge valve to stick open or closed and cause a CEL

so tru...gotta love the evap system.

[jh0n]

Well from reading this it sounds like u shouldn't top off. Thing is my wife & I have always topped off. First few tanks maybe not but after 3,000 miles on the car we started to. Normally I would go 1 to 2 gallon over the stop. Since we found we could go an extra 50 to 60 miles. she does 100 miles a day. So far we have done this for about 10,000 miles.

I`m with this guy, I do some big miles and it makes a difference. If I let it go at the first click, the guage needle moves off full almost straight away, if I cram every last drop into it, it`ll go way past 100 k`s before the needle moves. I`ve done this for the last 18 months and 45,000 k`s and had zero problems. I`ve done 750 k`s on a tank full, and in the right conditions I could do 800. I go out into the sticks at times when and where there`s not a lot of fuel to be bought, at times I actually take fuel in a container just in case. Just my .02, others can please themselves.

[Doohickie]

Ummm.... if you top it off and the gasoline gets in the evap system, it can lead to a very costly repair. I used to work for a company that manufactured OEM fuel tanks. Sometimes I'm guessing but this is something I *know*.

The dealer if the dealer finds out you've been topping off, this is *your fault* and therefore not under warranty and you have to pay. It's don't top off for a reason, guys

[TwiZ]

we warranty customers who we know top off...95% of the time when we get a canister thats contimated its by topping off...