[Jackpine]

One thing you can do, is monitor the Inst Econ (or Inst MPG). This tells you exactly what is happening at the moment, rather than looking at a "history" of what went on before. Now, I have no idea if the Inst MPG value is accurate, but it really doesn't matter, because all you really care about is "relative" behavior. If the numbers are "large" you know you're getting more miles per gallon than if the numbers are "small". In time, you can develop a "feel" for the engine sound, throttle position, and so on that matches the bigger numbers and, you should be driving economically.

Of course you still need to keep your eyes on the road, so don't "stare" at the Inst MPG gauge, which is going to be moving all over the place anyway. As pilots do, you have to develop a "cross-check".

Finally though, and I've said this before, wind is going to effect your fuel economy drastically at highway speeds. At 70mph, if you're driving into a 30mph headwind, the load on the engine will be ALMOST as bad as if you were driving 100mph on a calm day. You will see a drastic drop in economy driving into a headwind.

I don't even pay too much attention anymore to my mpg at each fillup. Instead, I'm more interested in the long term average over the last 1500 - 2000 miles. By taking that "long" view, you average out the headwinds/tailwinds, uphill/downhill, and city/highway driving effect. I've gotten about 14.8mpg averaged over the last 2600 miles (not towing).

And, to calculate your economy correctly, you need to make sure your odometer is accurate.

- Jack