What are the causes of abnormal engine idle noise?

1 Answers
CoreyLynn
07/30/25 5:49am
Engine idle noise may be caused by excessive clearance between parts, engine misfire, or engine knocking. Abnormal noise caused by excessive clearance between parts: Clearance between parts is an important factor affecting automobile assembly quality. When lubrication, temperature, load, and speed are constant, the abnormal noise becomes more obvious as the clearance increases. Some engine components produce noise due to increased clearance caused by wear. Engine misfire noise: Engine misfire mainly refers to one or more cylinders not working properly, manifested as obvious intermittent exhaust gas flow from the vehicle, severe shaking of the exhaust pipe, and clearly audible "popping" or thumping sounds from the engine.
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