Car throttle body

With the use of throttle valve you can determine the volume of air in the internal combustion engine and the volume of fuel that is supplied in the combustion process. Throttle valve is located in the inlet pipe and it is run using the "gas pedal". In modern engines an electronic control system of fuel feed is built-in and an electric wire controls the valve. In diesel engines there is no throttle valve system.

Since in modern engine fuel and air ratio should be the same, the volume of the mixture must exactly match the changed power. And that air that is supplied to the throttle valve is the first parameter. The driver determines it by a "gas pedal". Depending on the throttle valve position, necessary amount of the fuel is supplied. These two components are transformed into a hot mixture in the carburetor and fuel injection system and fed to the cylinders of the internal combustion engine. If the position of "gas pedal" does not match the number of revolutions, or if the engine runs at high speed during a light pressure on the "gas pedal", the problem can be in the throttle valve.

It is not difficult to replace the valve. But since the installation requires precision, let the workers of auto repair shop to do it. This mostly concerns modern cars with electric control valve. In many cases there is no need to replace the valve, but to re-adjust it. In our online shop you can find and order servo cylinder, camshaft, fuel filter, fuel pump, horn, pulse-scheme, and other spare car parts. Use search function or look through our catalogue of car parts.

How to detect throttle malfunction

Testing the component requires a specialized test bench. One should evaluate the working characteristics of the engine, and correctness of its operation. Besides, the Throttle position sensor should be tested. For a more thorough check, disconnect the throttle unit. After every 20 to 30 thousand km mileage, the component should be cleaned from dirt and oil.

Correctness of the position of the throttle is checked manually. Open and close the throttle several times. This should change the readings of the sensor. The clearance between the component and the body should not exceed 0.2 mm.

The service life of the component is unlimited. If it is regularly cleaned, its replacement may be not required within the entire service life of the vehicle.

You may notice that the Throttle requires diagnostics by the following symptoms:

• the engine operates incorrectly at idle speed;
• the cold engine misfires;
• vehicle accelerates unevenly when the gas pedal is pressed;
• detonation occurs when the engine is started;
• short knocks are heard in the exhaust system;
• the engine stalls at idle speed;
• a vehicle equipped with automatic transmission starts with jerks;
• the engine has lost power;
• increased fuel consumption.

The reasons of Throttle malfunctions

The most frequent reason of fouling the throttle is ingress of dust and particles of oil through the crankcase ventilation system, or through the air filter. Failure to clean the component in due time results in its jamming or non-tight closing.

The reason of the throttle letting too much air into the intake line may be its incorrect adjustment during installation, loosened fasteners, or intensive mechanical impact. For the same reasons, the component may get shifted during operation. Often, Throttle malfunctions are caused by damaged resistor of the built-in sensor.

The cable of a mechanical throttle loosens or breaks due to incorrect adjustment.

Throttle repair and replacement

Removing fouling, including oil, requires the use of an aerosol cleaner. Cleaning itself is not difficult, and you can make it yourself, however dismantling the Throttle unit requires help from an assistant.

Whenever the unit is cleaned, the gaskets are to be replaced. First, disconnect the corrugated air pipe. Then disconnect the accelerator cable after pressing the accelerator pedal until stop. After that, remove the hoses with the cooling liquid and the fasteners of the Throttle itself. If the latter cannot be fixed in the working position, or is poorly fixed, tighten the fasteners and calibrate the sensor. Calibration should be entrusted to a qualified specialist. If the throttle is mechanically damaged, or the supporting elements are worn out, it should be replaced.