The speed of a car is directly related to the fuel and air that is delivered to the engine. The mechanism that delivers both fuel and air simultaneously on most combustion engines today is the throttle body. The engine creates a vacuum when the piston goes into the down stroke in its chamber. Thus, when the throttle body opens up its chamber wider (through depressing the car's accelerator), more air enters the combustion chamber, followed by more gas. Sometimes it may be necessary to replace the throttle body due to damage or to have a larger throttle for increased engine modifications. Luckily, this is a fairly simple process.
Locate the throttle body between the air intake and the engine. On older cars, a carburetor may sit on top of the throttle body as well. Use crescent wrenches to loosen the four corner mounting bolts of the carburetor and then slide it off of the mounting studs.
Use pliers to disconnect the throttle cable (if applicable) or the wiring harness from the top of the throttle body.
Pull the air cleaner hose clear from the end of the throttle body. Use the crescent wrenches to remove the four mounting bolts still securing the throttle body to the engine. Slide the throttle body up and away from the engine.
