Allow MPG option to help with partial fillups
 

I sometimes work in New Jersey where people aren't allowed to pump their own gas. The attendants hurry and you can easily be a gallon or more low. I live in NY, and every other fill up I can actually fill the tank.

I was disappointed that you don't calculate a graph MPG entry after the complete fill. I saw the other postings and your policy. I'm a web/database programmer, I wish you'd add a vehicle option to: calculate MPG on first complete fill after partial -- it would make things a lot easier.

Thanks.

Can you explain how the logic/math you are suggesting would work? For example, how would we know how many gallons and miles to use in the calculations?

The only way I can this of this might work would be as follows:

Miles since last full fill-up/(partial fill-up gallons + next full fill-up gallons)

I think above might work but obviously we would not be able to calculate an exact per fill-up MPG. We could simply divide by two and give you the average.

Does anyone see anything wrong with this suggest math?

I think all hes asking is lets say you have 5 fillups that look like this

1) full fillup. 300 miles 10 gallons = 30mpg

2) partial fillup. 100 miles 1 gallon = ?mpg

3) partial fillup. 150 miles 1.5 gallon = ?mpg

4) full fillup. 50 miles 7.5 gallons = ?mpg

5) full fillup. 200 miles 8 gallons = 25mpg

Fuelly will say it doesn't know the mpg for fill up number 4, which is technically correct. It does not know the mpg for that particular fillup. However, it could do (100 + 150 + 50) / (1 + 1.5 + 7.5) and display the mpg for fill up 4 as 30 mpg.

I know this comes up a lot and fuelly has no plans of changing it, but I'm 95% sure this is what the OP is asking about.

^^^

If this is what he asks, and it really works this way (I really don't know, I don't have partials), then I second, it sounds doable and reasonable. There must be a way to show a 'virtual' FE for the whole pack (partials and the closing full fillup).

Please implement this! I know it's not per fill up, but it's nice to see that running average broken down, even if it's split between a partial fill up and a full fill up.

It's a running average, and that's a number I can work with. Besides, I do the math anyway, I just wish Fuelly would display it so I didn't have to.

Jon, partials still count towards your average. It won't effect the number of miles or gallons consumed that fuelly keeps track of. The only thing fuelly doesn't do (like in my example above) is display an average over the span of multiple fillups. For each tank, an MPG figure is calculated for THAT tank, which is impossible to do for a partial fillup, or a fillup where the previous entry was a partial.

The reason fuelly currently doesn't do this is to not confuse people. Using my above example, if fuelly displayed 30 MPG next to fillup 4, it's implying that the car went 50 miles, used 7.5 gallons, and somehow that equals 30 MPG; which is completely incorrect for THAT tank. If it displayed the 30 mpg figure, it would somehow need to specify that it is over the range of 3 different tanks. This is the part I think fuelly is not sure how to implement in an intuitive and user friendly way, so they just choose not to display the value.