Idle stop, on or off?

[John Ratsey]

I'm a believer that the auto stop does reduce fuel wasted and I get grumpy when it doesn't work (usually low battery). The HR-V handbook specifically notes that using the Eco mode increases the allowable temperature deviation from the target (which reduces the need for the engine to restart just for cabin heating / cooling). The same may apply on the Mk 3 Jazz although I don't recall it being mentioned in the book.