Symptoms of Engine Misfire?

1 Answers
DeAva
07/29/25 4:43am
Symptoms of engine misfire are as follows: 1. At idle, the vehicle body shakes noticeably. Observe the exhaust pipe outlet; the exhaust gas flow exhibits obvious intermittency, accompanied by severe exhaust pipe vibration, and a distinct "popping" or "thumping" sound can be clearly heard. 2. At low RPMs around 2000, the vehicle body shakes significantly with poor acceleration. The shaking sensation diminishes at higher RPMs, a phenomenon often related to the ignition coil. 3. Open the engine hood and observe the running engine. If the engine shows pronounced shaking that deviates from normal operation, with large vibration amplitudes, it is likely experiencing misfire. 4. After turning off the engine, manually touch the insulating ceramic body of each spark plug. For a four-cylinder engine, one cylinder may be harder to reach. A cooler temperature indicates abnormal operation in that cylinder. Alternatively, use a screwdriver to short-circuit the spark plug or disconnect the cylinder wire for a cut-off test. If the engine operation shows no significant change after disconnection, it confirms that the cylinder is not functioning. A vehicle can still start with one or two cylinders misfiring.
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