1. Knock will suddenly produce shock waves in the cylinder, impacting on all sides, causing strong vibration of the engine's piston, cylinder wall, connecting rod, crankshaft, etc., and irregular metal percussive sound;
2. The temperature of the cooling system is too high;
3. Incomplete fuel combustion and black smoke in the exhaust gas;
4. The engine power drops and fuel consumption increases.
Solution:
1. Reduce the ignition advance angle;
2. Use gasoline with a brand (octane number) in compliance with the regulations;
3. Remove carbon deposits in the combustion chamber;
4. If knocking occurs when the car is going uphill, switch to a low gear in time;
5. When the car starts, don't switch to the direct gear too early.
6. When knocking occurs due to excessive engine load, closing the throttle valve can also reduce knocking.
