12 13... Spark-plug faults

WARNING: This page does not describe the selected car, but rather 15 other vehicles, including the 2005 BMW 325xi, 2005 BMW 325i, 2005 BMW 325Ci, 2004 BMW 325xi, and 2004 BMW 325i. However, it is still accessible from the selected car via links, so may be relevant.

Evaluation of sparking period at idling speed.

Normal ignition voltage peak Spark plug is OK.
Low ignition voltage peak Small electrode gap.
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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