What are the reasons for the intake VVT operation failure and jamming?

[DiEmily]

Possible causes include damage to the intake VVT valve, oil passage blockage, excessively dirty engine oil, or abnormal engine oil pressure. Below is an introduction to VVT-related information: 1. Principle: Based on the engine's operating conditions, it adjusts the intake (exhaust) volume, valve opening/closing timing, and angle to achieve the optimal air intake, thereby improving combustion efficiency. Advantages include fuel efficiency and a high power-to-displacement ratio; the disadvantage is insufficient torque at mid-range RPMs. 2. Improving efficiency and increasing power: VVT technology can adjust the overlap timing and timing of the engine's intake and exhaust systems (partially or entirely), reducing fuel consumption and enhancing efficiency. The system, equipped with control and execution mechanisms, adjusts the phase of the engine camshaft, allowing the valve opening and closing times to vary with engine speed, thereby improving air charging efficiency and increasing engine power.