First phase: In so-called coast-down, activated by the driver taking his or her foot off the gas pedal (car coasts, TDI engine is shut off).    From Wordnik.com.  [Autoblog Green] Reference

The fact is: After just a short practice period the driver is able to adapt his or her driving style by integrating longer coast-down stretches and intuitively releasing the gas pedal - e.g. when entering towns or on freeway exits.    From Wordnik.com.  [Gizmag Emerging Technology Magazine] Reference