Back-seat drivers designed to save fuel
One of the more informative features of many hybrids is the expanded driver-information display. It shows power flow between the vehicle components and gives a rather accurate and real-time presentation of fuel-economy numbers.
Most vehicles have this capability through the engine-management computer to calculate similar information, but automakers don't always offer a driver display.
Now the aftermarket is responding with back-seat drivers that provide a variety of vehicle information and behavior. The one shown is called ScanGauge, but there are others from Davis Instruments called CarChip.
The devices operate differently. ScanGauge provides a display while CarChip can sound an alarm if fuel economy dips below preferred levels. CarChip also allows the driver to download the data to a personal computer.
Installation is easy and prices vary.
[Source: StarNewsOnline]
Reader Comments (Page 1 of 1)
Andrew 12:41PM (2/05/2007)
Driving below 129mph will also really help your fuel economy. How about something closer to 60mph?
Reply
Suman M Subramanian 2:07PM (2/05/2007)
Andrew, that's just an advertising pic, but your point is well-taken. I mentioned elsewhere that I installed a ScanGauge in my car over a year ago, and have achieved a mileage improvement of over 10%, due to modifying my driving style thanks to the real-time feedback.
Reply
Phil L. 2:35PM (2/05/2007)
To anyone who has used one of these gauges: How well do the displayed MPG figures appear to line up with manual calculation using odometer mileage and gas pump volume?
I wonder how tough it'd be to do something like this for pre-OBDII vehicles (the two vehicles I drive most often are both pre-1996 model year, so no OBDII interface).
Reply
MetroMPG.com 11:07PM (2/05/2007)
The ScanGauge is crack for the fuel economy obsessed. I got one as soon as I learned about them in Nov/05.
Phil: mine has almost always been within a couple percent of my "manual" calculations. That said, it has a correction factor you can optionally apply if you find it's consistently off by some amount.
If you're stuck with pre-OBD2, and want instant/average fuel consumption instrumentation, visit http://gassavers.org and look up "super MID". It's a home-brew device made by a Japanese Prius owner that calculates/displays consumption based on inputs from an injector wire and the VSS. And it can be (has been) adapted to other cars.
Reply
VTECPG1 9:11PM (2/10/2007)
Phil-- The ScanGaugeII works great. When you fillup it displays its own estimated fuel quantity to fill, you either accept that amount or shift the value a little so it can calibrate. Mine is usually within a percent or two of actual fillup quantity which can easily be attributed to different fuel-dispenser shut-off points. Between this and speed calibration ability, you can dial this in to match your own calculations. Though I've found it highly accurate without calibration in the four cars I've been using it in.
Obviously, the real-time MPG display is great. But I also love to watch/monitor fuel flow. It's interesting to watch the effects of turning on AC, rear defrost, headlights, etc. to the realtime fuel flow. For example, in my 06 Civic (non hybrid) at normal operating temperature, it idles at 0.2 gallons per hour (GPH), turn on the AC and it idles around 0.3-0.4 GPH, and the rear defrost adds about the same marginal increase as the AC. (wish I could run windshield defrost setting without AC)
The ScanGauge is also easy to move from car to car since it plugs into the standard OBD-II plug. I usually take it with me whenever I ride in a friend's car (not always recommended) for comparative fun.
Also, the daily summaries are cool too. Max coolant temp, max RPM, max speed, ave MPG, ave speed, moving time, fuel consumed, etc. These stats can be displayed by day or by a resetable trip period.
Easily the best automotive product I've ever purchased.
Reply