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Old 11-29-2012, 01:28 PM
unrealii unrealii is offline
Officially Welcomed to the 'Fest
Location: SoCal
Join Date: Mar 2011
Posts: 372
Mein Auto: 2009 335 6MT 'vert
6MT - Coasting in neutral hurts mpg?

Yesterday I started thinking about this while stuck in rush hour. Many times while driving I will hold down the clutch to let the car coast when engine power is not needed. However I remember reading something that these engines can cut fuel when coasting. Which led me to believe coasting in neutral is wrong:

1) The car has to use gas to idle the engine while in neutral
2) The car can cut fuel when coasting and in gear as the wheels are spinning the engine

My unprecise anecdotal tests barely confirmed this to be true

What are your thoughts?
2009 335i 6MT M-Sport AW/CR Convertible
2002 Toyota 4Runner 4wd
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