Originally Posted by
thecrow1981
Just releasing the gas pedal wil disable fuel supply to the engine.
Absolutely true!
But shutting off the engine to coast (transmission disengaged) is what saves the most amount of fuel, because the car coasts significantly farther without the drag caused by spinning the engine (engine braking).
Similarly, when you release the accelerator in a Toyota hybrid, the engine stops and you can modulate the throttle so there is no regenerative drag to maximize coasting distance.
Both are well-known techniques for maximizing fuel economy.
Of course if your goal is to slow down some while saving fuel, then simply releasing the throttle to decelerate is a good strategy (especially if you do it early enough that you avoid having to use the brake pedal). Of course, fuel injection resumes when the engine speed drops to about 1400 RPM. In the hybrid, the engine stays off all the way down to a full stop.
__________________________________________
View my fuel log 2014 Mirage ES 1.2 manual: 62.4 mpg (US) ... 26.5 km/L ... 3.8 L/100 km ... 74.9 mpg (Imp)