Now when you get in car and press gass button, your vehicle start immidiatly whithout engine launch process and delay.
Please add small 1-2sec dealy for engine start. It will be more natural, and looks more realistic as with helicopters and planes
Addtional feature: if engine damaged, vehicle have random chance to start engine
Look at GTA, FarCry3 and lot other games
Video of helis for example: http://www.youtube.com/watch?v=xwR0mfjwibc