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Home >> Mazda >> 2007 >> 6 Mazdaspeed >> Repair and Diagnosis >> Engine Performance >> System >> Symptom Troubleshooting [Engine Control System L3 With TC) >> No. 30 Spark Plug Condition >> Notes
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No. 30 Spark Plug Condition: Notes

POSSIBLE CAUSES DESCRIPTIONS

30 SPARK PLUG CONDITION
DESCRIPTION  Incorrect spark plug condition
POSSIBLE CAUSE 
NOTE:
  • Inspecting the condition of the spark plugs can determine whether a problem is related to a specific cylinder or possibly all cylinders.
Wet/carbon stuck on specific plug: 
  • Spark-Weak, not visible
  • Air/fuel mixture-Excessive fuel injection volume
  • Compression-No compression, low compression
  • Malfunctioning spark plug
Grayish white with specific plug: 
  • Air/fuel mixture-Insufficient fuel injection volume
  • Malfunctioning spark plug
Wet/carbon is stuck on all plugs: 
  • Spark-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 servicing the fuel system:
    • 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 ).

    CAUTION:
    • Disconnecting/connecting the quick release connector without cleaning it may possibly cause damage to the fuel pipe and quick release connector. Always clean the quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.