12 13... Spark-plug faults

Evaluation of sparking period at idling speed.

1. Normal ignition voltage peak Spark plug is OK.
2. Low ignition voltage peak Small electrode gap.
3. High ignition voltage peak Large electrode gap.

Evaluation of sparking period at idling speed.

Fig 1: Evaluation Of Sparking Period At Idling Speed

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Normal combustion period, spark plug is OK.

Fig 2: Evaluation Of Sparking Period - Normal Combustion Period

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Long combustion period, small electrode gap.

Fig 3: Long Combustion Period

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Short sparking period, large electrode gap.

Fig 4: Short Sparking Period

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