Causes of Idle Jitter of Wei Chai Engine

Wei Chai engine idling jitter may be the fault of the air intake system. The specific analysis is as follows:

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2. The intake pipe or EGR valve leaks air, the amount of air entering the cylinder is greater than the normal value, the mixture becomes thinner, and the dynamic performance of the cylinder decreases. If the EGR valve is not tightly closed, part of the exhaust gas will enter the cylinder, resulting in high residual exhaust gas, deterioration of the combustion situation, reduction of engine power, leading to engine jitter;

3. If the air flow meter or intake pressure sensor fails, the intake air quantity is inaccurate, and the fuel injection quantity of the fuel injection system is inaccurate, resulting in abnormal air quantity entering the cylinder and uncertain mixture concentration, resulting in engine jitter;

4. Idle speed control system is out of order. Idle speed control system mainly controls the air intake at idle speed, and increases or decreases the fuel injection quantity according to the air intake to achieve the appropriate air-fuel ratio. If the idle speed control system (such as throttle position sensor and idle valve) fails, the engine will not be able to achieve accurate air-fuel ratio control, and the engine power performance will decrease, resulting in engine jitter.