mpe488

ok... I have a 15.5 gallon tank, so if I get 200 miles to the tank (which I do more or less) I should be averaging ~13 mpg. I usually reset the trip when I top off the tank, but I thought I'd get a more accurate number if I reset it once and drove 1,000 miles, while keeping track of how much gas I had put in everytime I filler her up. So I did, after about 3 tanks I was astonihged to see that I had gotten ~15 mpg. And I continued to do so. But everytime I top it off I still cant get any more than 50 miles out of a quarter tank of gas.

Which of these methods is closer to my mpg figure?

LastYearZ28

fill it all the way up till it clicks off, reset trip, drive for as many miles as you wish. Go back to the exact pump and nozzle and fill up till it clicks, print the slip, divide miles on trip by gallons of gas bought= gas mileage.

200 miles
10 Gallons

20 MPG

ROCNDAV

iTrader: (100)

+1


Go to the same pump as he said.

LSGunZ28

iTrader: (8)

I always reset my trip and when I fill up gas until it clicks. I divide the gallons it took plus the miles.


The best I have done was 24.5 mpg That was going 1500-2500 RPM in 6th gear at speeds of 65-110 mph, with a 240 pound passenger. only a few times I had the car WOT and went 150 a couple of times. doing that I think 24.5 mpg is pretty damn good.


The worst I did was 11.5 mpg and tha was when I took the car racing the whole day and drove in traffic the rest of the tank.

Whisper

iTrader: (12)

27 MPG averaging 80mph with 3 people in the car- M6 of course.

mikerulzu

iTrader: (2)

I always reset the trip when I fill up, and just divide the number of miles on it by the number of gallons I use to fill up the tank. I do almost exclusively city driving, and have never gotten better than 18mpg. I've also only put 3k miles on it since I bought it 6 and a half months ago.

squealingtires

iTrader: (14)

Be carefull of the "clicks" that everyone is referring too. Fill your tank up to the very brim of the filler tube (rock the car to get all the air bubbles out and fill again and again untill no more bubbles come up. Drive around and return to the same pump and repeat the process. I'll admit that this is quite **** but it is as accurate as you can get. The "clicks is the automatic shutoff which senses gasoling at the nozzle. Foamy gasoline will trick the pump into thinking its full.(Ever wonder why it shuts off immediatly after you begin fueling up? Its caused by the gas foaming)

Drew's TA

I find going to the same gas pump and trying to top it of ALL the way to be quiet trivial. When you are trying to top it off and such you may only add .5 gallons at the most in my experiences. This shouldn't make THAT much of a difference in your calculations.
another thing that you can't take into account for is evaporation, and expansion of the fuel, these things can effect your readings.
The difference in .5 gallons is only about .7 mpg using 250mi/13gallons and 250mi/13.5gallonswhich is what i usually get.

Sgt. Spuds

iTrader: (1)

I usually don't fill my car all the way up, but I figured I might as well try it this time, I filled the **** out of my tank, gonna do the same as soon as its low.