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Old 09-05-2012, 09:44 PM   #27
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Originally Posted by Fresh1 View Post
I think the OP wanted to test the effectiveness of fuel cut-off during deceleration. This is why it's strange that the fuel consumption was higher in gear. If the fuel is cut off (regardless of engine RPM), it should burn NO fuel - vs. engine at idle speed in N. Anyone know what's goin' on? ...
Well, here's a theory (to answer my own question ;) ...
Maybe when decelerating in gear, the vacuum generated by the piston downstroke sucks in blowby gasses back into the cylinder/combustion chamber, and then sends them out through the exhaust during the upstroke. So, maybe the Scanguage just "thinks" more fuel is being burned at this time, but it isn't? ...
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