Dreams about animals show us the positive and negative qualities of an animal as a metaphor. All animals have good and bad sides to them. People do to- we can call it our lower & higher natures. When we understand the way a quality is showing up in a dream then we can begin to integrate the positive more and more into our life.
So a dog has the quality of friendship & loyalty. A car is a symbol of the way to get to where you are going. A mall is a symbol for many possibilities & options. Water is a symbol for relationships & life. So to see a dog in a car going no where which needs more water, is a message to you that your True Self, your Higher Self, is very loyal and friendly. But something right now is sort of making you feel like you are going no where (because the car is parked & not driving.) What your friendly & loyal self wants now is lots and lots of opportunities for building positive relationships. Then it will be like the dog getting all the water it wants and needs.
Does that make sense?
Healing With Dreamwork 