Incorrect mpg

[pb]

The average MPG calculation uses total distance driven and total fuel volume filled. So that could be why you're seeing a calculation that looks too high.

[RussTaylor]

Thanks pb, I'll look into it in a bit

Draig, if I wanted to get good economy I'd probably aim more towards a 500, they look fun

[RussTaylor]

Pb, my odometer reading is fine, it went to 45k kilometres so is in sequence, so it seems to be down to bad calculating again. Hopefully given another ten fuel ups it'll be right again. Just about to fill it up again so I'll see what that does. Thanks

[pb]

oh yeah, I see that now. huh, misread it.

[pb]

So it looks like you've gone 1518.8 km on 135.7 litres. That gives us 31.6 MPG.

[RussTaylor]

Ok I just put another fuel up in, and we're back to 24.9 which is right Seems that the partial fuel up confused it. There is no way in the world my car will do over 30mpg unless you're pushing it. I'll look at the numbers later to see how it's getting 1518.8km and 135.7 litres to see where the discrepency is, thanks.

Great site, and thanks for all your help BTW not sure it's anything to do with you but the mobile site is no longer allowing me to enter decimal places on fuel ups, it's not available on my Galaxy S3. I don't know if that's an S3 fault or something changed on the mobile version, but thought I'd say.

Thanks again

[RussTaylor]

Ok I did the math and I can see that the last partial fuel up was what confused it

So ideally if your last fuel up is partial then the average calculation should ignore it, but otherwise wait till the next full fuel up and it's good to go.

Also if I was being a real pain my last full fuel up could get it's mpg from the full fuel up + the last partial and the odometer difference since then. I didn't get a mpg reading for the last one.

Anyway not criticising, lots of great features on the site, I just found the 300ZX comparison page which was quite interesting.

Thanks again

[pb]

On the Galaxy S3, yeah there isn't anything we can do about that on our end. You can bring up this page on your phone:

http://m.fuelly.com/disable-numeric-keypad.gas?id=1

This will set a cookie that tells Fuelly Mobile to use the standard keypad for entering numbers. That's about the best we can do on this end.

When you mark a fuel-up as partial you won't get an individual MPG for that fuel-up or the next one. Once you have two full fuel-ups in a row you'll start getting that number again. The reason is that Fuelly calculates that number using the difference from full. When you add a partial, there's no full tank volume to calculate from. And if we just use the partial tank, it makes the tank look bigger than it is in reality—you'd get a misleading number.

Here's more info: Why do I have to fill the tank all the way up every time I buy fuel?

[RussTaylor]

Pb, thanks for the fix, much appreciated.

I was just thinking why not aggregate partial fuel ups with the next full tank, along with mileage? You could run on half a tank for ten fill ups, then do a whole tank and find out how that changes economy.

Anyway I won't take any more of your time. Thanks again, thanks for the site.

[MMUK]

I already suggested that, but it was rejected (they want to keep things simple, one tank = one mpg figure).