What is a throttle Body – what does it do?
The throttle body is what controls the volume of air entering into the engine and is located at the beginning of the intake manifold at the start of the plenum chamber. From there it is distributed down the four “Runners” to the cylinder head. The size of the throttle body directly affects the volume of air entering the vehicle and as such, can have dramatic effects on throttle response, acceleration, torque and overall horsepower. The TPS switch is usually located on one end of the unit and on the other end is the throttle cable. The Mitsubishi / Proton / Hyundai units generally also have an idle speed control motor (ISC unit) on the bottem half of the throttle body with choke water hoses to raise / lower the idle speed when cold and when items like the air conditioning etc kick in. There is also normally two other adjustments – a air bypass idle speed screw which allows you to raise / lower the base line idle speed and the butterflyh stop adjustment which adjusts the point where the
