Car Humper 

One who likes to drive fast and apply breaks abruptly, Horrible driver, Break-shoe raper

Dude drive slow you're such a "Car Humper"!
I hope you're a good driver 'coz my last driver was a Car Humper.

Car Humper by Rave patty August 2, 2011

car hummer 

A blow job that occurs in a car.

We were driving on 101 when my girlfriend leans over and gives me a car hummer

car hummer by Bungalow Bill February 16, 2002