In this part of the verse, J.ReaL orchestrates an auto-assassination by using what is essentially the fire & gasoline from the first two lines to blow up the car (a Kia Sport, of all things) holding the rappers he’s going against.
This is a metaphor to describe his destruction and defeating of the rappers that he feels are wack. Blowing up the car is his way of saying he’s going to take down the things holding rappers inside their respective “lanes”; which are current trends, styles, popular sounds, etc. With the current state of popular rap being the way it is, it’s no wonder why this particular car is so fitting.