Vanden Plas L6-4.0L (1990)
Spark Plug: Testing and Inspection
Checking Spark Plug For Wear, Damage, Or Deposits
1.
Remove spark plug wire and spark plug.
Visual Spark Plug Inspection
2.
Inspect the spark plug for:
a. Improper gap
b. Carbon deposits
c. Cracked center electrode insulator
d. Burned or worn electrodes (may be caused by):
da. Excessive mileage
db. Lean fuel mixture
dc. Advanced ignition timing
dd. Loose spark plug
de. Plug heat range too high
df.
Insufficient Cooling
