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Old 02-05-2012, 03:27 PM   #2 (permalink)
Piwoslaw
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Join Date: Oct 2008
Location: Warsaw, Poland
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Svietlana II - '13 Peugeot 308SW e-HDI 6sp
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Quote:
Originally Posted by Hepialid View Post
I have only tended to use this system when I know I am going to be stationary for any more than 15 - 20 seconds. I am aware that restarting even a warm enginer requires a spurt of fuel.

Does anyone know if there is any available information to show what is the minimum stationary (i.e engine off time) needed to cancel out the engine restart fuel consumption?
From what I've read, in fuel injected cars the "spurt" of fuel at startup is negligible. Someone here calculated (I can't find the post, this was quite a while back) that killing the engine is worthwhile whenever your stop is longer than 2-3 seconds. (The actual number was less than a second, but you should factor in 1-2 seconds for driver reaction and actual startup.)

Often you can kill your engine while coasting towards a red light, before actually stopping - this how second generation Start-Stop systems work.
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