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Old 08-06-2007, 04:05 PM   #3
Even Steven
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Join Date: Jul 2007
Location: New York
Posts: 26
Quote:
Originally Posted by JCL12
What do you all think of this:

My box is a tiptronic. Despite the auto-trans, my box has some pretty darn strong engine braking. (I am not used to this)

When coming to a spotlight or going down a hill, what do you all think of putting the car into neutral to eliminate engine braking and coast with less friction? Although it'll definetly save me some gas, is frequent "shifting" from drive to neutral going to cause premature wear and tear on the transmission?

Thoughts and comments?
Actually, it will not save you any gas. A little known fact about modern engine management systems is that they have the ability to cut off the fuel pulse entirely when coasting, such as a long downhill grade. Now, I'm not a Porsche mechanic, so I'm not 100% sure that Porsche does this, but I do know for a fact that most other manufacturers program their engine management systems to do this in order to raise their average fuel economy.

So the next time you're coasting down a hill, if you put your transmission into neutral, remember that you're forcing the computer to send fuel to your engine to keep it idling. If you were in gear instead, the fuel pulse may be shut off entirely by the engine management system, thus increasing your fuel economy.

If you doubt this, just do a little bit of research on the Internet and you'll discover it's true.
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