Premature Electrode Wear - Preignition Damage
PREIGNITION DAMAGEPreignition Damage:
Excessive combustion chamber temperature can cause preignition damage. First, the center electrode dissolves and the ground electrode dissolves somewhat later. Insulators appear relatively deposit free. Other possible causes include ignition timing over-advanced and incorrect spark plug heat range.
Spark plugs are designed to operate within a specific temperature range, called spark plug heat range. Variations in thickness and length of the center electrode and porcelain insulator change how fast the plug can dissipate heat and determine the plugs heat range.
Determine if the spark plugs are the correct type, as specified on the VECI label, or if other operating conditions are causing engine overheating.