The One

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Fall weather MPG update

It's getting tougher and tougher to maintain 40+ mpg in the colder fall weather here in PA.

I just filled up today.  The last time I filled up was Sep 29 - 5 weeks ago!  For this tank the mpg guage read 40.4 mpg.  It started at 42 mpg and went steadily down as the weather got colder.  It just takes longer for the engine to heat up and my work is only about 7 miles from home.

The guage is still reading high.  My calculated mpg based on gallons used is 38.14 which is 5.6% less than the guage reading of 40.4.

Since shortly after I got the car, my average mpg according to the long term guage is 40.7 and the calculated mpg is 39.14 - a difference of -3.8%.

I'm still loving the car!


Improving the MPG bar graph

The FFH has a bar graph that you can display in the dash that shows MPG over a 10, 20, or 60 minute period.  There are 10 bars so each bar is the average mpg over a period of 1, 2, or 6 minutes:Each bar shows mpg over a 6 minute period

During a recent 600 mile trip to Maine I realized that this gauge is not as useful as it could be.  It frequently happens that there is a bar that has a very low mpg next to a bar with very high mpg.  Imagine the bar graph is set for 10 minutes (so each bar shows mpg during a minute) and the time period for a bar is just beginning.  You happen to be gliding the car in EV mode 50 feet to a stop at a traffic light.  Say this takes 15 seconds.  Then you wait at the light for 45 seconds.  The bar appears and its over 60 mpg because you were in EV mode or stopped for the whole minute.  Yeah!  Then you accelerate from the light and head up a hill for a minute, going 1/2 mile.  The next bar comes up and the mileage is dismal - 20 mpg.  Looking at the bars, you think that's ok - after all, you have one 60 mpg bar next to the 20 mpg bar, the average of those two must be pretty good!

But its not, you only went 50 feet during the first bar's time period.  Since mpg is calculated by dividing miles traveled by gallons used, the overall mpg of those 2 minutes is 20.15 mpg.  The appearance of the bars suggests that you should weight each bar equally, but you should not.

I would love to have the option to display a bar graph based on MPG per mile traveled, rather than per minute traveled.  That would be much more useful.  Each bar would indicate the mpg over a given distance, say 1, 2, or 5 miles.  Each bar would be directly comparable.  You could look at the graph and visually get an idea of your recent mpg by looking at the bar heights.  You would also be able to directly map the bar heights to mileage along your route - eg a low bar might indicate an uphill climb on your commute.


FFH in the wild

I was driving to work today (miserable, rainy) and as I glided up to a light I thought I saw that familiar rear end.  Could it be?  Did it have the tell-tale "hybrid" logo?  Yes!  It was a light blue Ford Fusion Hybrid!  I waved at the driver but I doubt he/she saw me.

I watched to see how he would pull away from the light - usually I can make it to work from this light in EV mode, but you need to start slow over a little rise at the light before going downhill.  He took off from the light though and left me to creep over the rise.

First FFH (besides mine) spotted in the wild!  :-)


Tips for good gas mileage

I've got some experience under my belt now with driving the FFH for good gas mileage.  I haven't been able to achieve the phenomenal 84+ mpg that Wayne Gerdes and Ford did in driving 1440+ miles on one tank, but I've been able to average a respectable 41 mpg or so over the last 6 days / 175 miles, which means I still have 3/4 of a tank left.  Here are some tips/techniques I've developed for achieving good mileage without going to extremes.

  1. Go downhill.  I get better mileage on the way to work (51 mpg) than on the way home (36 mpg). Today, I stopped for coffee on the way to work and from the coffee shop (near my house) to work I got 71 mpg.
  2. Avoid hills.  You can get much more consistent results and achieve longer pulse and glides (see below) when its flat and open.
  3. Avoid highways.  The engine turns on at 47 mph and gas mileage goes down.
  4. Go on the highway.  Too much stop-and-go traffic, or hilly back roads, reduces mileage so the highway can be a better choice.
  5. Drive like an old lady.  You must try and stay in electric (EV) mode whenever possible, which means pulling away from stops slowly, coasting whenever possible, and braking slowly to allow for regen.
  6. Drive like a race car driver.  Take corners fast so you don't lose as much speed coming out of the turn.  The FFH handles nicely around corners.
  7. Creep along slowly.  When you're in a parking lot or driving up your driveway, take it slow and don't get out of EV mode.  Let the car slow down topping a hill if it means you can stay in EV mode.
  8. Drive as fast as possible.  When you've got a good hill to build up speed and a good run-out at the end or another hill, build up some speed on the way down so you can coast as far as possible.
  9. Keep it in "Drive".  When you've built up too much speed, you can scrub off some speed productively by braking lightly enough to activate regen without actually using the brakes.
  10. Put it in "Neutral".  If you've got a decent stretch of road to coast on, you'll get more distance if you slip the transmission into neutral, but you won't get any brake regen.  You can put the FFH back into "Drive" at any time without hurting the transmission.
  11. Pulse and glide.  Select a speed range (eg 30 - 45) and accelerate slowly up to 45 then coast down to 30 (with or without going into neutral - see above) and repeat.
  12. Feather the gas pedal.  Let it off a little just to get back to EV mode. Keep your speed up as high as you can without getting out of EV mode.
  13. Use the Empower gauge - you can see at a glance how close you are to turning on the gas engine.
  14. Turn off the A/C.  I have noticed a difference with A/C on or off in how easy it is to stay in EV mode.  You can also turn it on but leave the fan on low.
  15. Be patient.  It takes discipline not to revert to old habits.  But be sensitive to the cars behind you too and don't force them to get good mpgs ;-)

With these techniques you can improve gas mileage.  But it takes concentration and can be frustrating.  At times I just want to step on it and get moving!

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