Is there a way to calculate the average for a trip. Say my total average is 16 but if my trip from Sunnyvale to SF City i want to see how much I get for that trip. On my Subbie I could get the current average after resetting the speedo for that trip. On ISF this does not work, any ideas?

 

You can always do it on paper. Fill up your tank full (~16 gallons) and jot down your starting odometer reading before you depart and when it comes time fuel again, do the same with the mileage. It's not going to be exact, but it'll give you a close approximation of what your MPG is like for the trip. But I thought there would've been a way to see it on the navi if not on the gauge cluster.

 

Try a Scangauge. It's a gauge, a trip computer and it scans and resets codes. $159 on eBay. I've had one for a couple years and use it all the time.

http://www.scangauge.com/

 

The on-board device isn't very accurate sometimes. You can't beat doing it with a spreadsheet. This is from a solo cross country trip with my 350.

 

If you are willing to clear you overall average, you can do it that way. Just clear the AVG (not the Tank AVG) counter by holding down three seconds on the display button. This will give you an average for point A to point B.

 

I found a good on line spread sheet along with the lowest gas prices in my area. Take a look at www.gasbuddy.com to find the page for your local area. It has my fuel usage for the last seven years.

 

found a way to reset the Average. Go to the display and go to teh screen where it shows the average. Hold the display button for 3 seconds and the average is wiped out. That way one can get the average for that trip.