How do you see average MPG for one trip?

Not unless you are willing to write down the numbers and do the arithmetic. I have sometimes wished for two mileage computers myself.

 

Unlike Honda, Toyota has elimintated this possibility. Nor can we get a lifetime average. These are the kind of programming options which could easily be provided by Toyota, but so far haven't been offered.

 

The scan gauge give you 4 more mpg readouts: tank, current, today and yesterday.
Today and yesterday are defined by 8 hours between starts. Mine reads a bit low but you can calibrate it.

But after recording over 15 tanks to see how accurate my mfd mpg readout is, I now just reset it whenever I feel like measuring a trip. My fill up spreadsheet handles the tank averages, and I care far more how I just did on my last trip, and for regular trips whether I did better or worse than average.

 

I just bought a program from silverleaf that I use in my motorhome. It taps into the engine computer to give me all of the engine and transmission info on my laptop while rolling down the road. I can set up several odometers to record a trip, a day, a week, a month,a tank or any other distance or period of time. I can view them all at the same time along with other engine info. ( boost, % of load, temps. etc ) It has made me a more effecient driver. When I can go from 8 mpg to 9 1/4 mpg, that's a 15% improvement. ( @ $3.39/ gal, it still costs $300 to fill it up)

I wonder if someone could come up with a similar program for the Prius that would feed into a PDA. It's interesting to compare the results of different driving conditions. Of course, if I wasn't so lazy, I could do it all with pencil and paper.


Doug

 

Scan gauge is the obdII display meter I use primarily to show tach and temperature readouts. It is inexpensive and there are lots of posts here about it.
The Can View also looks good and I may switch to that when it is available.
You need something with temperature at a minimum if you live in an area with winter temperatures.

 

[/quote]
As other people are writing, it is an easy calc as follows.
Please take note(ODO and displayed mileage value) at each point you would like to know.
Then, do the math to find how much gas used since reset.
Now, you know the section gas used and the distance, then do the math for the section mileage.

Following my data driving on a highway at 91km/h using CC.

point_____ODO__disp_km/L__calc_L__sect_L__sect_km__sect_km/L
============================================================
Point-A___88km__28.6km/L__3.08L___0.00L______0km
Point-B__116km__27.5km/L__4.22L___1.14L_____28km___24.53km/L
Point-C__131km__26.1km/L__5.02L___0.80L_____15km___18.73km/L
Point-D__193km__29.5km/L__6.54L___1.52L_____62km___40.70km/L
============================================================
Note: calc_L=ODO/disp_km/L

Additional information...
You can see very various section mileage number even driving at 91km/h constant speed.
The reason is there were altitude(potential energy) changes.

Assuming we need 106mL gas to get the potential energy for 100m high, I did math as follows...

point_____Alt__AltChg_m__AltChg_L_adjust__sect_km__adjust_km/L
============================================================
Point-A___634m_____0m_____0.000L__0.000L______0km
Point-B___761m___127m____-0.135L__1.007L_____28km___27.82km/L
Point-C__1009m___248m____-0.263L__0.538L_____15km___27.88km/L
Point-D__ 346m__-663m_____0.703L__2.226L_____62km___27.85km/L
============================================================

Then, the adjusted section mileage number is constant like I drove very flat road.

Enjoy,
Ken@Japan

 

Did you also enter a program that adds and then averages the milage of both the motorhome and the prius. I knoe ehy you have a prius, so you can save enough gas to also drive the motorhome.

 

I too use the ScanGage to plot the trip milage, milage for the day and yesterday and now life time i.e. I am not resetting the tank milage so it will calculate the life time from now on. I also keep manual calculations.