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A More Perfect Fit: Toward a More Perfect MPG, Part 2


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Jackman's Almost Perfect 2007 Honda Fit

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By Michael Jackman
Louisville Bureau
The Auto Channel

Welcome back to A More Perfect Fit, my Auto Channel column covering how to make a nearly perfect car, The Honda Fit, even more perfect. This column continues my series on how to max out the Fit’s miles per gallon.

Last time I covered five common sense driving techniques guaranteed to improve your mileage, contributed by Richard Kahn, owner of Earth In Upheaval Auto Repair of Sebastopol, Calif. [LINK] This time I’m covering three ways the Fit Sport Automatic can be used to nudge up your mpg.

What’s the Fit’s Fuel Efficiency Rating?

How fuel-efficient is the Fit? According to the 2007 dealer sticker, my Sport AT (automatic transmission) model boasted 37 highway and 31 city. I was impressed until my first tank of city driving gave me only 24 miles per gallon. Then I was bummed.

Recently, I saw a new dealer sticker advertising a less impressive, but probably more realistic, 34 highway, 27 city. Why the change? According to Chris Martin of Honda Public Relations, the EPA adopted a new method of calculating miles per gallon. You can find the explanation on www.fueleconomy.gov. This EPA Web site explains that the improved method tests for “faster speeds and acceleration, air conditioner use, and colder outside temperatures.” (check out this site to see how most auto models fare under the new formula.)

The good news is that I’ve hardly seen a tank as low as 24 mpg since I started using these techniques. If you follow the guidelines in this series, you too will consistently beat the sticker ratings.

The Ideas Behind the Tips

Lower RPM = Higher MPG. It all comes down to rpm: the faster your engine turns, the more gas it uses. In general, to get the most efficient fuel economy, lower rpm as much as possible (the best result being when the car is not driven at all). One exception is when you coast. In that case the engine is still turning, but you’re not using any fuel.

You can tell exactly how your driving affects rpm by hooking up a device such as the ScanGauge II (pictured below), which connects to your car’s OBD-II (on-board diagnostic system, version 2) data port, and displays its engine data. (Read more about OBD-II at www.obdii.com).

For instance, when warmed up and in Park (with all switches off), my Fit’s engine turns at an average of 750 rpm, according to the ScanGauge. Switch on the lights and the rpm climbs to about 850, to meet the new power demand. Same with the AC. Other devices, such as the radio, fan, and wipers, don’t appear to add an additional load on the engine. But that extra 100 rpm uses more gas, and lowers mpg. That’s why hypermilers leave off the AC, sweating their way to improved mileage. I’ll discuss that practice in my next column.

Higher Gears = Higher MPG. In the Fit you can drive at 35 miles per hour around town in your choice of either third, fourth or fifth gear, fifth having the lowest rpm, but the least torque. Aside from those times you need a lower gear (with more torque) to climb a hill or accelerate quickly, your goal is to drive in the highest gear possible. And if you own a Honda Fit Sport (not the Base model) with automatic transmission, you get a manual transmission thrown in: two paddles on the steering wheel, marked (-) on the left and (+) on the right (see picture, below).

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These two paddles on the Fit AT’s steering wheel let you manually change gears.

Did you think these paddles were a neat but useless toy? So did I, until I learned to use them effectively.

The Techniques

In Drive, Use the Paddles to “Nudge” the Gears: In Drive, as long as your rpm is in the range for a gear, you can downshift by clicking the (-) paddle toward you, or upshift by clicking the (+) paddle toward you. Usually, the automatic transmission logic will switch back to the gear it senses is best after a few seconds. But when you’re accelerating, you can nudge the gears up. Here’s how it works:

When the gears change, you can feel the car respond, see the tach needle fall and hear the pitch and the volume drop with the rpm. Drive with a heavy foot and the upshift takes place at around 2,800- 3,000 rpm. Drive with a lighter foot and you’ll experience the same change around 2,500 rpm. Finally, accelerate very gently, and the gears change closer to 2,000 rpm. Conditions don’t always let you use the gentlest driving though, such as when you’re taking off from a stoplight surrounded by aggressive traffic, you’re late for work, or you’re just impatient with boring, economical driving techniques. At such times, when you see the tach needle rise over 2,000 rpm, click the paddles to upshift into third, fourth then fifth gear. You’ll beat the car’s logic to it and shave off some gas consumption.

Note: If you don’t have enough speed to change gears, you’ll see the number you were trying to change to flash a few times in the tachometer display. Try again in a quick moment.

Use S-Mode Effectively: By driving in “S-mode” (Sequential Shift Mode), you can use the paddles as a manual transmission. According to the Owner’s Manual, in S-mode you can upshift as early as: second (dead stop), third (over 6 mph), fourth (over 21 mph) and fifth (over 30 mph). Since the speed limit in most in-town driving is 35 mph or above, you can drive most of the time in fifth gear, maxing your fuel economy. You can even start in second from a dead stop by clicking the (+) paddle twice. This technique will also give you more traction on snow or other slippery surfaces.

On the highway you’ll almost always cruise in fifth gear, downshifting to fourth when you need power to pull the Fit up a steep incline or quickly accelerate to pass another vehicle.

Watch out for two gotchas in this mode. First, you have to remember you’re in it. Although S-mode will remind you it’s on by displaying your gear in the tachometer with an “m” (for manual) next to it, if you usually drive in automatic, you’ll probably space out and forget at the first stop light. The next sound you hear will be your engine redlining as you gun the accelerator, because you forgot to upshift out of first. So save yourself from embarrassment, and keep your mind on the fact that you’re in S-mode. (Note: when you slow down or brake, S-mode will downshift for you.)

I call the second gotcha, “Where’s the paddle?” Remember, they’re mounted on the steering wheel, so when you turn, the paddles turn, too. I’m going to put red tape on the (+) paddle, so I can find it when I need it. If you’re like me, until you get the turning-paddle thing down cold, be ready for some unexpected gear shifts.

Undocumented: Use Cruise control in S-mode: This trick also only works on a Sport AT. On a recent trip from Louisville to St. Louis, I threw the car into Cruise Control, thinking consistent speed would raise my mpg compared to what my unrobotic right foot could do. I was disappointed. Whenever the transmission logic decided the car was going up a steep grade, it downshifted to fourth. But often, I didn’t think the incline was that steep.

A few weeks ago, during a trip to Cincinnati I decided to experiment with cruise-control and S-mode (there’s nothing about using the two together in the manual). I got a delightful surprise: S-mode cruise control holds the gear. Not only that, but it accelerates and decelerates more gently, even allowing the car to slow down one or two miles per hour when climbing hills. Both facets: holding the gear and accelerating more slowly, save gas. As a result I averaged more than 40 mpg for the experimental portion of the trip. And if I ever needed more power to climb a steeper grade, all I had to do was click down to fourth.

This trick also works in town. On a long stretch, you can cruise as low as 35 mph in S-mode, fifth gear. Doing so, I watched my in-town driving exceed 32 mpg on a horrible, unavoidable stretch of road (I had to stop at nine traffic lights within three miles). So try S-mode cruise control: it’s the best kept secret about driving the Fit Sport AT.

Can You Switch Between Drive & S-mode on the Fly?

This question comes up a lot in the forums. Based on my experience, you can switch between Drive and S-mode any time. When going from S to D, the gear seems to stay the same. When going from D to S, the transmission seems to downshift one gear.

To sum up, if you own a Honda Fit Sport with an automatic transmission, you can use the paddles in at least three ways to help increase your fuel economy. In my next column, I’ll cover the pros and cons of some of the much-debated hypermiling tips. In the meantime, be a boringly safe driver, and spend some money on maintenance to accelerate toward a more perfect mpg. And as always, I welcome your comments.

Michael Jackman is a Louisville, Ky. based writer and professor of writing at Indiana University Southeast. More info at.mjfreelancer.com