What Does Engine Knocking Feel Like?

1 Answers
OAdriana
07/25/25 5:22am
Engine knocking produces irregular metallic knocking sounds like "clunk" or "clang" inside the engine. Here is extended information about knocking: 1. Prevention methods: Retard the ignition timing and reduce combustion pressure. Under certain conditions, the combustion in gasoline engines can become abnormal, with high-frequency pressure curve fluctuations and drastic dp/dt value variations near top dead center reaching (dp/dt)max=0.2Mpa/us. At this point, the flame propagation speed and flame front shape change abruptly. This phenomenon is called detonation, and knocking is the external manifestation of detonation. 2. Principle: In gasoline engines, the air-fuel mixture enters the combustion chamber during the intake stroke. The spark plug compresses it during the compression stroke, and after ignition, the pressure generated by combustion is converted into the engine's operating power.
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