On 07/20/2017 05:59 AM, Mad Roger wrote:
I'll check out these references which are in the back of the article.
Allen, Mike. "3 Gadgets That Really Work." Popular Mechanics. DIY Auto.
December
2008.http://www.popularmechanics.com/auto...23.html?page=2
Allen, Mike. "How to Monitor Your Fuel Economy in Real Time on the Road."
Popular Mechanics. June 9,
2008.http://www.popularmechanics.com/auto...o/4267957.html

That link didn't work for me but

http://www.popularmechanics.com/cars...12057/4267957/

appears to be the same article.

"There are some tech tricks you can use to help monitor your fuel
economy as you drive. I'm fooling around with a couple of devices right
now. I just installed a Scangauge on my motorcycle. This $180 device
plugs into the On Board Diagnostic System (OBD II) port under the dash
of virtually any post-1996 car or light truck. It operates as a scan
tool (much more on that here), so it gives me trouble codes and
streaming data, but it also works as an electronic gauge cluster and
trip computer. I can track battery voltage, coolant temp and sundry
while tooling down the interstate. But one feature is invaluable: the
instantaneous fuel economy readout. It gets fuel quantity data from the
injection timing--the longer the injectors are open, the more fuel they
squirt. It's amazingly accurate, too."

The ScanGauge can be calibrated for the actual rolling circumference of
the tires. It does instantaneous, which I don't find to useful, as well
as daily or tank mileage reporting. On a fillup it predicts the gallons
you will put in. That's the least accurate because I always use the
automatic shutoff but even that is usually within a couple of tenths of
a gallon.

Using the car odometer and a notebook with your gas purchases is
strictly for the Luddites. It's like measuring acceleration with a stop
watch and the seat of your pants when you can use an accelerometer.