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Old 01-15-2009, 01:52 PM   #1 (permalink)
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Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 22,234

Blackfly - '98 Geo Metro
Team Metro
Last 3: 70.09 mpg (US)

MPGiata - '90 Mazda Miata
90 day: 52.07 mpg (US)

Winter beater Metro - '00 Chevrolet Metro
90 day: 61.98 mpg (US)

Fancy Metro - '14 Mitsubishi Mirage top spec
90 day: 58.72 mpg (US)

Even Fancier Metro - '14 Mitsubishi Mirage top spec
90 day: 70.75 mpg (US)
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"Pulse and DFCO" (deceleration fuel cut off) doesn't work

I've seen a few descriptions of people mis-applying the pulse and glide technique on various web sites & forums.

More than once I've read of people describing the technique as simply repeatedly accelerating and letting off the accelerator (to achieve fuel cut). The logic being, "if I'm in fuel cut, it must be more efficient!"

Of course the penalty of being in fuel cut is that you've got engine braking, and the vehicle won't travel nearly as far as it will in a neutral, engine-off glide.

One person did a "pulse and DFCO" experiment and posted the results of his efforts on his web site. He noted 2-4% worse fuel economy based on the before/after "A" portions of his on-road A-B-A comparison over 575 miles for the "B" portion (using p & dfco in the "B").

Full details (see Part 5 of the page):

Honda mods: Ecomodding my $800 Honda Fit 5-speed beater
Mitsu mods: Oops, I did it again! Bought another cheap, 3-cylinder Mirage. Mods in progress...
Ecodriving test: Manual vs. automatic transmission MPG showdown

has launched a forum for the efficient new Mitsubishi Mirage - fuel efficiency info for Geo Metro owners - electric car conversion on a beer budget
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