I don't know how true it is, but I've read (can't remember if it was in this forum or another) that topping off leaves fuel in the filler neck that is more prone to evaporation. I don't know the accuracy of this information.

Another thing I read was that fuel is more dense when it's cold. So it's best to fill up in the morning, before the sun heats up the ground. But at 15 gallons, I don't see this being of any major difference.

But since we're on the subject of filling up! My wife took my car on Saturday to go run errands and meet a friend for a movie. The fuel light came on while she was out, so she filled up the car. Not only did she pay 11 cents more per gallon than what I would have filled it up for, but she also "forgot" to write down the mileage! I've been doing that in front of her for over two years now. I don't know how she forgot. But it wasn't a problem. The FCD is programmed to reset after each fill-up! All I had to do was check the history screen to see the mileage.

 

Can you explain that a bit more? Is there a standard history display and something that normally resets when you refuel, or is it something you set up yourself?

 

I don't think the HCH has this feature. The HAH w/Navi has it under the INFO screen.

 

The salesman told me when I bought the car (we went to fill up the car together) that you are NOT supposed to top off. He was told by the head tech guy there. It seems to be more of a problem now that gas prices have risen....

Tan: Unfortunately, your attempt at consistency only makes your fillup have more gas at an inconsistent rate. If one nozzle gives 10.7 gallons, and another gives you 11.2, adding one or two gallons still gives you the EXACT same difference in gallons (i.e. half a gallon) than had you left it alone. The problem here is HOW much it pumped in the first place, not how much you pump after. Since there is no EXACT way to know how much gas you used up from the last fill up, there is no EXACT way to know how much you should need to fill up, so you can't even compensate for it. Its a problem I know, but I don't really worry about it. There is no real solution for it unfortunately....unless you maybe use the SAME PUMP at the SAME station, which I by the way do.

 

My apologies but not to beat an already dead horse to death....Over time as you add more and more tanks full to your personal data base, the numbers will magically smooth out so no matter what you do, top off, or stop at the first click your MPG's will be very consistent. All that happens is you may get more or less miles per tank depending on the fill. Anyone who has studied stat's will verify this, me included. Just look at our fantastic data base of MPG data. There are so many miles and gallons, one click or two more or less will not make a big difference. The only thing that may happen is you can damage the vapor recovery system by infusing the charcoal with liquid fuel and cause more air pollution (gasoline vapors)...Not a good thing.

 

From the Honda tech topping off will damage the emissions equipment with the gas vapors. So what Ralphdog said is true. This happens with the newer cars because of the computers etc.

 

Well, what else are dead horses good for?

 

GLUE.