what if you have a guy who trys to save peoples lifes from bad axidents but he never saves them and they die and people think he is killing them so they are mad at him and chasing him and it makes it even more not possible to save people because people are chasing him! he would not be a killer but they would sentance him do death at the end and he would cry and yell that he was just trying to help

Isn't that what Stephan Kings "Christine" was ?

..in a way it was....my idea is that the ghost not only haunts one car but "jumps" from car to car after it has killed the victim....

I dunno...could turn out pretty good! ;)