Forklift Throttle Body - The throttle body is part of the intake control system in fuel injected engines in order to control the amount of air flow to the engine. This particular mechanism works by placing pressure on the operator accelerator pedal input. Usually, the throttle body is situated between the intake manifold and the air filter box. It is normally connected to or positioned close to the mass airflow sensor. The largest component within the throttle body is a butterfly valve known as the throttle plate. The throttle plate's main task is so as to regulate air flow.
On nearly all automobiles, the accelerator pedal motion is transferred via the throttle cable, thus activating the throttle linkages works in order to move the throttle plate. In cars with electronic throttle control, also called "drive-by-wire" an electric motor controls the throttle linkages. The accelerator pedal is attached to a sensor and not to the throttle body. This sensor sends the pedal position to the ECU or Engine Control Unit. The ECU is responsible for determining the throttle opening based on accelerator pedal position together with inputs from other engine sensors. The throttle body has a throttle position sensor. The throttle cable is attached to the black part on the left hand side that is curved in design. The copper coil positioned near this is what returns the throttle body to its idle position once the pedal is released.
The throttle plate revolves in the throttle body every time the operator presses on the accelerator pedal. This opens the throttle passage and permits more air to be able to flow into the intake manifold. Normally, 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 generate the desired air-fuel ratio. Generally a throttle position sensor or also called TPS is attached to the shaft of the throttle plate in order to provide the ECU with information on whether the throttle is in the idle position, the wide-open position or "WOT" position or somewhere in between these two extremes.
So as to control the lowest amount of air flow while idling, various throttle bodies can have valves and adjustments. Even in units which are not "drive-by-wire" there would usually be a small electric motor driven valve, the Idle Air Control Valve or likewise called IACV that the ECU utilizes to be able to control the amount of air which can bypass the main throttle opening.
It is common that a lot of automobiles have a single throttle body, even though, more than one can be used and attached together by linkages in order to improve throttle response. High performance cars like the BMW M1, along with high performance motorcycles like for instance the Suzuki Hayabusa have a separate throttle body for every cylinder. These models are called ITBs or "individual throttle bodies."
A throttle body is similar to the carburetor in a non-injected engine. Carburetors combine the functionality of the throttle body and the fuel injectors into one. They operate by combining the air and fuel together and by modulating the amount of air flow. Cars that have throttle body injection, that is known as CFI by Ford and TBI by GM, locate the fuel injectors inside the throttle body. This allows an older engine the chance to be transformed from carburetor to fuel injection without significantly changing the engine design.
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