First of all getting yourself away from him is the best thing that you could have done.  But since you have not said that you are amrried then I worry that you will be charged with theft if stopped with the car. So I would have it returned to him (maybe by another family member) and then I would get a restraining order against him for ou and your child.  He can not avoid child support but if you really want him out of your life speak with a lawyer about terminating parental rights (which will stop support).  Good luck.