What are the symptoms of gasoline engine knocking?

1 Answers
Raymond
07/29/25 11:34am
Gasoline engine knocking manifests as intermittent metallic sounds from the engine in mild cases, while in severe cases, it produces continuous metallic knocking noises. Below are the specific causes of gasoline engine knocking in automobiles: 1. Excessive carbon buildup in the combustion chamber: This increases the compression ratio (creating high pressure) and can generate hot spots or sparks on the carbon deposits, leading to engine knocking. 2. Overheating of the engine: High ambient temperatures or poor engine coolant circulation can cause the engine to overheat, resulting in knocking. 3. Low octane rating of the fuel: Higher fuel octane ratings provide better anti-knock performance. Engines with high compression ratios have higher combustion chamber pressures, making them more prone to knocking when using low-octane fuel.
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