i dunno i fill it up untill it gets annoying afeter every second the pump clicks off. never had a problem with vapor collecting nor do i smell any or see any spilt fuel anywhere... i have filled it up to the brim before and nothings ever spilt out from expanding temps. now hills yes i wil belive that...

but i would not rely on pumps shutting off all at the same time. unless you used the same station same pump every time you filled up. ive had it before where i would put it in turn it on full blast and it didnt shut off one time and fuel came out all over the place...so dont rely on pumps shutting off at the same time cuz they dont...

i know that the CEL will come on if the gas cap is not tight enough on newer cars...but i have never heard nor have any of my mechanic friends that too much fuel will cause the CEL light to come on...

I use a small notepad to write down things like date, time, odometer reading, tripmeter reading, and location. At the gas station, I stick the gas nozzle into my gas tank, pull the trigger, set the trigger lock, then while the gas is being pumped, using the data on my notepad and the calculator feature in my cell phone, I'm already calculating the number of miles I drove and waiting for the pump to finish pumping to enter in the number of gallons used to calculate the fillup to fillup overall average fuel economy. I only fillup until the first click because if I fill up with more gas, then I'd have to not only recalculate the fillup to fillup overall average fuel economy, but since I base my fuel economy calculations assuming that the fuel used since last fillup is the same as the amount of fuel I just pumped, mathematically that would make the gallons higher, therefore the fuel economy lower. :)

The pump shuts off when the gas foams back up the filler tube and that can happen at different filll levels depending upon how fast the pump you are using pumps the gas. I get another gallon in my tank after the first click so that is another day or two of driving / 10% more in the tank.

Full top off on our Hondas. Run it right up the filler neck, thru the baffle, right up to the lip of the filler tube. Same with the Ranger. No cel's, no codes and no wee wee. From 1st click off. I can get 2 more gallons in the cars.

Only cars Ive ever had that didn't like full top offs where GM. Some would wee wee up front where the canister was or back in the tank area.

psy

I fill all the way up. after it clicks I proceed very slowly till I can see/hear the fuel coming up to the top. I have had no problems with this method.
One click fills can vary quite a bit from tank to tank, at least in my experience. But I guess over time your average mpg should be the same.

At Costco, there is a sign on the pump
 

Paraphrasing: Save money and save the environment, don't top off

I stopped topping off when I started shopping there. Haven't had a spill since.

Does anybody only fill 1/2 way to try to carry less weight? With long commutes and construction here, I don't dare.

M

ma4t

Ive seen that sign and heard the argument for years on topping off.

We are not on the EPA's dirty air list here. I work to not fill up on ozone alert days. As well as not mow the yard. If I do have to fill up on alert days. I do it in the early morning hours.

The way I look at it. I go thru less fill up cycles in a year due to toping off. That extra 2 gallons gets me from 75 to 110 miles more driving per tank in the Civic. Also the pump I use. Yes I use the same pump 98% of the time is very controlable. I never have a spill. Thats not to say there arent spills at my filling station. The oil burners are the worse. Its nothing for them to blow a qt. to gallon out on the ground. It happens weekly.

psy

with the sunfire i fill up at the same station and at the same pump everytime. well i try to, sometimes there are other people so need to go to a different pump.
i pump it all the way to the top of the tank, right to the top of the filler neck. i have had no problems with CEL, i do spill sometimes but, with our pumps we can vary the speed at which the gas comes out, so i go as slow as i can. that works most of the time.

Slow-fill
 

We don't have any tricky vapor recovery pumps, so I generally rest the nozzle in the tube about an inch away from the spring (so it's essentially straight in the filler tube and not jammed in at an angle).

Then, the fun part -- the first notch of 3 on the pump handle and wait (I'm making the assumption that a slower fill is a bit more accurate). In the meantime, I can clean out the car or find a pen to record the mileage :rolleyes:

In KC we do have Ozone Alert days, so I usually wait until the evening to fill anyways. I haven't "topped off" a tank for years -- too much trouble with the vehicle's vapor recovery and the Ozone issues -- plus I've had splash-back too many times to admit -- even on full-first-click's.

RH77

It's 4 miles from work over the bridge to Missouri.
I try to go to the same pump, set it on the slowest fill speed, & stop filling at the first click.
With the price difference from Illinois, I can usually buy a free Powerball ticket.
I'm hoping the pursuit of FE will make me a millionaire!:eek: