Counting Down the Gallons

A "fuel consumption display" on the Acura RDX gives drivers real-time readouts

| | A Toyota hybrid's fuel consumption display|

Last weekend, while PopSci's official natural-gas-powered Civic, was busy being photographed by Honda, some friends and I took the Acura RDX that Honda gave us as a temporary replacement on a ski trip in the Catskill Mountains. The RDX is a sleek, turbocharged SUV, and considering that the nicest car I had driven previously was probably my rusty '89 Corolla, I naturally felt like I was driving some sort of space vehicle.

Let's just say there was never a dull moment inside. Between squeals of delight when the rear-mounted night-vision camera would engage with a shift into reverse, downshifting around winding mountain passages with the semiautomatic shifter paddles, and entering new destinations into the navigation system just to hear Mrs. RDX talk to us, it's a wonder we didn't accidentally drive right off the side of of some deadly precipice.

The feature that was most fascinating to an automotive Luddite such as myself, however, was easily the least flamboyant of the bunch. It took me a while to notice it, but on the way back I finally saw the "fuel consumption display" tucked in below the digital odometer. What this little wonder does is give the driver a real-time readout of the current fuel efficiency in miles per gallon. Unsurprisingly, the RDX is no fuel-sipper (sporting a dismal 19 mpg city/23 highway rating), so it was interesting to see the gauge swing dynamically from a high end of 40 mpg during a 75mph highway cruise to a bottom end in the single digits during sudden accelerations or braking.

Emphasizing the appeal of this little gauge was an article I stumbled on today detailing the practice of "hypermiling," a driving style meant to squeeze the highest possible fuel efficiency from any given vehicle. The story profiles Wayne Gerdes, the man who originated the term along with many of hypermiling's core techniques, such as coasting in the draft of semi trucks, frequently killing the engine while rolling, and driving "brakeless." What got Gerdes started on this whole train of thought was, coincidentally enough, the very same fuel-consumption display in his wife's Acura SUV. It turns out this is a pretty standard feature these days, especially on hybrids like the Toyota Prius and Honda Insight, and there's a whole community of people who boast of their high FCD-display readings on the forums of sites like greenhybrid.com.

Now the replacement space-ride is gone and I'm back to taking the bus, always wondering about its mpg rating as it struggles along its route. I can see how this could get addicting. —John Mahoney

Link - Mother Jones [via kottke.org]