Just joined the Prius club with a 2012 Prius 4. This is also my first Hybrid and I'm still in the learning phase of my new toy. One thing I noticed a few times now is that when I'm stuck in traffic or waiting for a light to turn green, the engine shuts of completely (I expected this) but it turns itself back on after a couple of mins. even when I didn't move at all and my foot is still firmly on the brake. Is this normal and why? Who can explain this to the confused? happy to join this forum !