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No.30 Spark Plug Condition: Notes

SPARK PLUG CONDITION - DESCRIPTION AND POSSIBLE CAUSE

30

Spark plug condition

DESCRIPTION

Incorrect spark plug condition

POSSIBLE CAUSE

NOTE:

Inspecting spark plugs condition can determine whether problem is related to a specific cylinder or to all cylinders.

Wet/carbon is stuck on specific plug:

Spark-Weak, not visible
Air/fuel mixture-Excessive fuel injection volume
Compression-No compression, low compression
Faulty spark plug

Grayish white with specific plug:

Air/fuel mixture-Insufficient fuel injection volume
Faulty spark plug

Wet/carbon stuck on all plugs:

Spark-Weak
Air/fuel mixture-Too rich
Compression-Low compression
Clogging in intake/exhaust system

Grayish white with all plugs:

Air/fuel mixture-Too lean
WARNING:
- The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before performing the fuel system services:
  - Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel.
  - Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE REPAIR PROCEDURE" and "AFTER REPAIR PROCEDURE" described in this manual.
    (See BEFORE REPAIR PROCEDURE .)
    
    (See AFTER REPAIR PROCEDURE .)