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ransley ransley is offline
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Default Coasting in neutral doesn't save gas

On Jul 30, 12:21*pm, (Doug Miller) wrote:
In article , ransley wrote:

On Jul 30, 9:29=A0am, "HeyBub" wrote:
So says Popular Mechanics:


http://www.popularmechanics.com/cars...ting-in-neutra....


'Course the author is assuming an internal combustion engine. Presumably
with a hybrid, the coasting actually CHARGES the batteries, thereby
increasing gas mileage. I'm not even going to get into external combustio=

n
engines...


I dont buy it, it isnt a gasolene consumption issue, when coasting in
gear the engine is not moving at idle speed, the extra rpms are a drag
on the transmission and lower mpg,


That doesn't make any sense at all. If the injectors are delivering no fuel,
none of that matters. The engine isn't consuming any fuel, but the vehicle is
still moving forward: mpg is infinite.

the trans also has more drag being
in gear. He is only thinking gasolene not drivetrain friction loss.


According to the article, coasting in neutral burns gas, coasting in gear
doesn't. If that's correct, then OBVIOUSLY you use less fuel coasting in gear.


Coasting the motor idles right, even coasting at 70 downhill the motor
is only getting gas to idle, but in gear at 70 it wont be 6-700 rpm it
will be maybe 1400 rpm, the increase is drag through the drivetrain
not gasolene.