Ok, so they didn't make hybrids back in 1997 when I purchased my Civic HX and it doesn't have a digital fuel consumption display. I've always enjoyed calculating my gas mileage and trying out different techniques for road trips to see what the results are, but without an fuel consumption display to do quick, controlled tests, you're kinda limited in what you can research.

Then along came the ScanGauge. It plugs into your OBD2 port and reads the fuel consumption from the ECU. This sounded like the perfect toy for me to play around with so I bought one. It apparently doesn't quite compensate for the HX's lean-burn mode, but the information is still valuable, and I set out to chart the steady-state fuel consumption at various cruising speeds in 5th gear. Using 3 different roads and doing runs in each direction to balance out slope, I came up with the following results:



Supposedly the lean-burn mode only engages at light load covering speeds upto somewhere around 60-65mph. My chart would seem to probably follow-along with that. I think that the figures are all a bit pessimistic up until you get to the 70+ mph range where they seem to be a bit more accurate. The flat spot from 60-70 seems to be kind of a transitional speed range where maybe it was sometimes able to lean-burn, and sometimes running stoich.

At any rate, most all of you should own hybrids that actually report the fuel consumption correctly regardless of engnie mode, so I was wondering if anyone else has collected data like this? I spent about 2 hours total doing it (2 runs in each direction for each speed, 1-2 mile long stretches) since none of my "ideal condition" roads for each speed range were all that close to each other. Still, for 2 hours of my time, I feel like I collected valuable data that I can use every day, even when I don't have my ScanGauge in the car. Has anyone else done such experimentation and data charting?