Escape Clunker

On the weekend, you went on a trip with their parents. You put on the back seat of the car and tightly fastened belt, so you will not run away and not hurt if the car something happens. Daddy's car is a real clunker, but the other had not. You are staying near the forest, and your parents have gone to look for a source of water, and you are left in the car. You waited a long time and it seems that the parents do not come back. Flee their machines.