NO.29 SPARK PLUG CONDITION [MZI-3.7]
NO.29 SPARK PLUG CONDITION (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES
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If malfunction remains, inspect related Service Bulletins and/or On-line Repair
Information and perform repair or diagnosis.
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If vehicle is repaired, troubleshooting completed.
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If vehicle is not repaired or additional diagnostic information is not available,
replace the PCM.
(See
PCM REMOVAL/INSTALLATION [MZI-3.7]
.)
29
SPARK PLUG CONDITION
DESCRIPTION
Incorrect spark plug condition
POSSIBLE
CAUSE
Wet/carbon stuck on specific plug:
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Spark-Weak, not visible
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Air/fuel mixture-Excessive fuel injection volume
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Compression-No compression, low compression
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Malfunction spark plug
Grayish white with specific plug:
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Air/fuel mixture-Insufficient fuel injection volume
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Malfunction spark plug
Wet/carbon is stuck on all plugs:
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Spark-Spark weak
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Air/fuel mixture-Too rich
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Compression-Low compression
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Clogging in intake/exhaust system
Grayish white with all plugs:
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Air/fuel mixture-Too lean
NOTE:
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Inspecting spark plugs condition can determine whether problem is related
to a specific cylinder or possibly all cylinders.
WARNING:
The following troubleshooting flow chart contains the fuel system diagnosis
2008 Mazda CX-9 Grand Touring
2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9
Microsoft
Sunday, November 15, 2009 10:10:06 AM
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