What happened to the fault light of Sonata Lingxiang engine?

1, poor combustion state: weak car.

2. Engine knocking: the car is weak and the engine is noisy.

3. There is obvious knocking sound.

In the case of 1, some engine fault lights will be on, and some will not. In the second and third cases, the engine fault light will inevitably light up.

Internal causes of engine fault light;

The fuel quality is not good.

The inside of the engine cylinder is not clean and there is carbon deposit.

The above analysis is for reference.