What are the reasons for high engine idle speed?
1 Answers
Reasons for high engine idle speed: 1. Idle control valve failure: The normal idle speed of an electronic fuel injection engine is determined by the idle control valve. The electronic control unit calculates signals such as engine speed, temperature, throttle switch, and air conditioning switch, then adjusts the idle control valve to open the intake bypass channel or directly increase the throttle opening to increase the intake air volume and raise the engine idle speed. If oil contamination or carbon deposits cause the idle control valve to stick or the throttle to fail to close properly, the electronic control unit cannot accurately adjust the engine idle speed. 2. Intake system leakage: Under normal circumstances, the intake air volume must be strictly limited. If there is a leak in the intake pipe, the air flow sensor cannot measure the actual intake air volume, leading to inaccurate control of the intake air volume by the electronic control unit and unstable engine idle speed. 3. Fuel injector leakage or blockage: If the fuel injector leaks or is blocked, it cannot spray fuel according to the instructions of the electronic control unit, resulting in a mixture that is too rich or too lean, causing poor operation of individual cylinders and unstable idle speed.
