Forklift Throttle Body - Where fuel injected engines are concerned, the throttle body is the part of the air intake system which controls the amount of air which flows into the engine. This mechanism works in response to operator accelerator pedal input in the main. Normally, the throttle body is positioned between the intake manifold and the air filter box. It is usually attached to or located close to the mass airflow sensor. The biggest component in the throttle body is a butterfly valve referred to as the throttle plate. The throttle plate's main function is to be able to control air flow.
On several styles of cars, the accelerator pedal motion is communicated through the throttle cable. This activates the throttle linkages that in turn move the throttle plate. In vehicles with electronic throttle control, likewise referred to as "drive-by-wire" an electric motor controls the throttle linkages. The accelerator pedal connects to a sensor and not to the throttle body. This particular sensor sends the pedal position to the ECU or also known as Engine Control Unit. The ECU is responsible for determining the throttle opening based on accelerator pedal position along with inputs from other engine sensors. The throttle body has a throttle position sensor. The throttle cable connects to the black portion on the left hand side which is curved in design. The copper coil positioned next to this is what returns the throttle body to its idle position as soon as the pedal is released.
Throttle plates rotate within the throttle body each and every time pressure is placed on the accelerator. The throttle passage is then opened to permit more air to flow into the intake manifold. Typically, an airflow sensor measures this change and communicates with the ECU. In response, the Engine Control Unit then increases the amount of fluid being sent to the fuel injectors so as to produce the desired air-fuel ratio. Generally a throttle position sensor or otherwise called TPS is fixed to the shaft of the throttle plate to provide the ECU with information on whether the throttle is in the wide-open throttle or likewise called "WOT" position, the idle position or somewhere in between these two extremes.
So as to regulate the lowest amount of air flow while idling, several throttle bodies may have adjustments and valves. Even in units which are not "drive-by-wire" there will usually be a small electric motor driven valve, the Idle Air Control Valve or IACV which the ECU uses to regulate the amount of air that can bypass the main throttle opening.
It is common that several vehicles have one throttle body, even if, more than one can be utilized and attached together by linkages so as to improve throttle response. High performance cars like the BMW M1, together with high performance motorcycles such as the Suzuki Hayabusa have a separate throttle body for every cylinder. These models are referred to as ITBs or otherwise known as "individual throttle bodies."
The carburator and the throttle body in a non-injected engine are rather the same. The carburator combines the functionality of both the throttle body and the fuel injectors into one. They could control the amount of air flow and combine the air and fuel together. Vehicles which include throttle body injection, that is called TBI by GM and CFI by Ford, locate the fuel injectors inside the throttle body. This allows an old engine the chance to be converted from carburetor to fuel injection without really altering the design of the engine.
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