Sorry for this simple ques. I notice sometimes the engine cuts off upon stopping while other times the engine remains running. Can this be explained? Thanks.

It is supposed to.
It's a good thing.
It saves gas and lowers emissions.

It will only autostop when the car is warmed up and a few other requirements are met.
Look up autostop in your manual.

Enjoy the silence!

Need fewer troops to support.
Drive a hybrid.
Best tank 71.65 MPG.

Before this car I spent two years learning hypermiling on my 2004 HCH1.

Autostop is a beautiful thing. When you see the green "AutoStop" blinking on your dash, that means the engine is off. It unnerves the wife but puts a smile on my face every time

the autostop will engage when the vehicle comes to a near stop, usually under 8 mph. it will remain engaged until you release the pressure on the brake pedal. this basically means that your engine is no longer running and you are using energry from the battery pack to operate your accessories. there are a few factors as to when this happens:

-vehicle has to be up to normal operating temp
-the front window defroster can't be turned on

for more info on the autostop feature check your owner's manual....