A car may refer to the course of life but not if it has been in storage for an indefinite period. It often pertains to something else: your body. Specifics may include headlights for eyes, radiators for the mouth, tires for hands and feet, you get the idea.
The question in my mind concerns how old you were when you first owned a car and how old you are now. What physical trait has remained unchanged and lacking development (i.e. in storage) despite any debt incurred by physical neglect. The guy whom you know casually should have gotten rid of it would be your Ego. Because it's in the back of your mind, it's tucked away in memory without enough emotive impetus to immediately be brought to the Preconscious. Because it lacks this impetus, the Unconscious prompts you in its attempt to dislodge this memory trace for re-ordering in the process of mundane dreams.
If an aspect of your body has been neglected, it may be due to diet, exercise, proper balance between leisure and rest, or even setting a routine for balance; and if so, may not be as weird as it initially appears.