need help

[grsshpr1]

I think I might be doing my gas logs wrong does anyone know a perfect way of explaining it? Would be greatly appreciated
With a 13 gallon tank
My first fill up was 11.55 I got 373 miles
I only was able to get 20 bucks worth I got 5.58 gal and 177 miles
My next fill up was 11.65 gal and got 400.1 could've gone more
but didn't want to damage my fuel pump.

Just filled up today for 12.14 gallons
thanks for your help

[benfrogg]

Quick and dirty-
You don't need to know the size of the tank.
Simply input the date, distance traveled (clicking your odo at each fillup), and the exact gallons number on the receipt. (put both digits after the decimal) You don't need to add the price of fuel, although I do because I think it's interesting to keep track of fuel prices over time. Additionally, it makes your log harder to "fake."

On fillups, expect variation from tank to tank. The only way to limit variation is to always fill until the first click and stop. No topping off. Let it get down as far as you feel comfortable, and repeat. Try using the same station/same pump if you can too.
Either way, expect your real FE number to be a 3 tank average. That's as close as you'll get. Then, you can start monitoring your FE overtime.
Hope that helps.
B

[GasSavers_BEEF]

not sure if you mean the math or the method of keeping up with everything.

the math is as simple as it sounds miles/gallon (miles divided by gallons)

373/11.55=32.29...
177/5.58=31.72...
400.1/11.65=34.34...

if it is the method, I fill to the click and reset my trip mileage. when I fill again, I fill back to the click and that gives me miles for the previous fill. this is flawed as there could be slight fluctuations but I have heard that over about 3 tanks, it averages out. several people have suggested using the same gas station, same pump, same time of day but I am a bit impatient for that so mine will stay slightly flawed. I can live with that.

hopefully some of this is of value to you. good luck.

***edit***

beaten to the punch, was typing while the previous post was posted. maybe it just reiterates what I was saying (or what he was saying). anyway, you see that the accuracy is in the averaging.

[trollbait]

Whenever I have put in a small amount, I just make a note of it. The next time I actually fill up, I add those short fill miles and gallons to the tank fill up in the gas log entry.

Or another way to say it, I don't reset the tank trip odometer after adding, say 5 gallons. The next time I fill the tank to a click, I record and reset the tank odometer, and add the previous fuel amount to the recent fill.

Since most cars now have multiple trip odometers, I guess you could easily track those short fills. Just note it in the comments. You might note a difference in mileage in short fills. I purposely underfilled the Prius with fuel bladder because economy got better as the tank emptied.