Coasting to a stop in neutral with a modern manual (and in some instances automatic) transmission might not actually save you as much gas as keeping it in gear. Many modern engine management systems sense deceleration and negative load while the car is in gear and cut off fuel from the injectors, allowing the turning drive shaft to keep the engine going. Shifting into neutral while decelerating means the system has to keep the engine running with gas.
by Zahnarzt on June 06 2009
this tip works for 84% of voting Fuelly members.