IACventtiili

IACventtiili is a Finnish term that translates to Idle Air Control valve in English. This component plays a crucial role in the fuel injection system of many internal combustion engines, particularly those with older electronic fuel injection systems. Its primary function is to regulate the engine's idle speed.

The IACventtiili operates by controlling the amount of air that bypasses the throttle plate and enters the engine intake manifold at idle. When the engine is idling, the throttle plate is mostly closed, which would normally lead to a very low or stalled engine speed. The IACventtiili opens to allow a controlled amount of extra air into the engine, thus maintaining a stable and appropriate idle RPM. This control is often managed by the engine control unit (ECU) based on various sensor inputs, such as engine temperature and load.

A malfunctioning IACventtiili can manifest in several ways. Common symptoms include rough idling, stalling at idle, difficulty starting, or an engine idle speed that is too high or too low. Dirt, carbon buildup, or mechanical failure can cause the valve to stick or become unresponsive, preventing it from adjusting the idle air flow correctly. Cleaning or replacing the IACventtiili is a common repair procedure for these issues.