Under review

The distances at Bi-Fuel are not calculated properly

aaronoberthuer 3 years ago updated by Adrian 3 years ago 3

First of all, thanks for this awsome app!

Now to the issue: When I use a Bi-Fuel-car (and have correctly activated two fuels) the distance count is seperated between the fuels.

For example I started at 85000 km and refuel CNG and petrol (95+). Than I drive some weeks and only refueling CNG. Than also needed to refuel petrol additionally to CNG. So I did two entries with the same date and the same distance.

Now comes the trouble: The app refers the entry for petrol to the former entry for petrol and not to the last entry. Therefor it calculates a faulty value for the distance (it takes the actual one and compares it with the one of the last petrol refill. This is wrong. So also the resulting calculation of the petrol consumtion is wrong (about 0,41 Liter per 100 km :-).

Here the table:

Date/Fuel/DistanceCounter/Calculated additional distance/amount of fuel







2017-10-16/Petrol/85013km/ /FirstFullRefill#1/1Liter

So the error is to substract the petrol-distance-values from one another.

But the distance value is independent from the kind of fuel. Therefor the calculated additional distance should be always generated by using the last and the second last distance value.

It would be fantastic if you could correct this. :)

And by the way: CNG ist handeled in Kilogramm, not in Liter (but this is only manicure).

Best regards,


Under review


It's not a bug. But I'm using this way to calculate consumption. Most of users wanted this way to do that. Why?

In most cases Petrol+LPG - petrol is just fuel that is used for run your engine, not to drive the whole time. So Fuelio is calculating distance per tank - that's why you see distance also per tank.

For calculation, there is additional option to exluce distance for example whne your LPG/CNG tank is empty and you are using petrol. In this case you can reset your trip counter and later add this value to "exclude field" to get real consumption for CNG/LPG.

For 3,94L/100km consumption. This is correct when you think about this this way. You have used 3,94 per 100km using petrol - because most of the time you've been driving on LPG/CNG.

But I'm thinking about adding this as an option (in other settings). But then calculation will be really bad. To get real consumption for petrol - you need to add two full fillups one after another and in the log you'll see this. But as overall setting - this is actually true. You are not using petrol as your primary fuel so consumption is low (and it should be).

What you say is true in some way however for the true consumption of petrol the user should only use trip odometer. For the main source (in this case LPG/CNG) both odometer or trip odometer can be used

Not sure I understand.

True consumption is calculated with excluding some km.

I know that many LPG users are driving on LPG, when it ends - they are switching to petrol and when your LPG ends - reset trip counter to calculate how many km you have driven on petrol. With the LPG fillup you can simply just enter here this value.