Mpg Question

[alositha]

since the purchase of my new prius I have done my second fill up. for a 35.89 litres I have done 507 mile. this include a two hour trip on the motor way and the rest is just around the town. so my calculated MPG (imperial) is 59.22 but the tripometer gives me 53MPG is this done using US gallons? calculation gives me 49MPG (US). i am bit confused!! have you got any ideas?

cheers

[Sagitar]

since the purchase of my new prius I have done my second fill up. for a 35.89 litres I have done 507 mile. this include a two hour trip on the motor way and the rest is just around the town. so my calculated MPG (imperial) is 59.22 but the tripometer gives me 53MPG is this done using US gallons? calculation gives me 49MPG (US). i am bit confused!! have you got any ideas?

cheers

I find the trip value for m.p.g. unreliable. It is never accurate and the inaccuracy is not consistent.

I filled up yesterday when the trip was showing a tank value of 61.7 m.p.g. The real value (calculated) was 57.86 m.p.g.

However, I cannot get to grips with your calculation either.

35.89 litres is about 7.89 UK gallons or 9.48 US gallons and that gives either about 64.25 m.p.g. (UK) or 53.48 m.p.g. (U.S.)

[Jolly English Gentleman]

The tripometer is certainly optimistic in the 2nd Gen. Car tells me I have returned 53.3mpg since opening an account with Fuelly. The actual return is somewhat lower, but still pretty damn good

Is this a full fill up? The tank is larger than 35.89 litres - I think both the 2nd and 3rd gen have a 42 litre tank. Was some of your 507 miles done on petrol that was in the tank before your last fill up?