Green’s Dictionary of Slang

(US) one who hijacks an automobile or robs its driver.

1995		G.A. Haywood ‘And Pray Nobody Sees You’ in Woods Spooks, Spies and Private Eyes (1996) 183: I’m gonna need a description of the carjacker and the license plate of the car.
1997		G. Sikes 8 Ball Chicks (1998) 63: The child’s father was murdered by car jackers five years ago.
2017		T. Pluck Bad Boy Boogie [ebook] [P]olice had emptied their guns into a Newark carjacker.