Concorde V6-201 3.3L VIN T FI (1993)
Spark Plug: Technical Service Bulletins
Spark Plug - Insulator Discoloration
NO: 08-28-93
GROUP: Electrical
DATE: Jul. 9, 1993
SUBJECT:
3.5L Engine Spark Plug Discoloration
MODELS:
1993
(LH) Concorde/Intrepid/Vision
1994
(LH) LHS/New Yorker
DISCUSSION:
The brown stain on the spark plug insulator above the metal shell and below the spark plug boot is a common occurrence. This condition is not a defect
and does NOT require the spark plugs to be replaced due to this appearance.
The ignition system generates a corona in the area of the spark plug not covered by the spark plug boot. The electrical capacitance of the spark plug
creates an electrical field in the region of the spark plug. The electrical field generates ozone from the air. Ozone is a very active form of oxygen that will
combine with ever present contaminates that form the harmless brown stain.
POLICY: Information only.
