NO.29 SPARK PLUG CONDITION [MZI-3.5]
DESCRIPTION AND POSSIBLE CAUSES
available, replace the PCM.
(see
PCM REMOVAL/INSTALLATION [MZI-3.5]
.)
29
SPARK PLUG CONDITION
DESCRIPTION
Incorrect spark plug condition
POSSIBLE CAUSE
Wet/carbon stuck on specific plug:
z
Spark-Weak, not visible
z
Air/fuel mixture-Excessive fuel injection volume
z
Compression-No compression, low compression
z
Malfunction spark plug
Grayish white with specific plug:
z
Air/fuel mixture-Insufficient fuel injection volume
z
Malfunction spark plug
Wet/carbon is stuck on all plugs:
z
Spark-Spark weak
z
Air/fuel mixture-Too rich
z
Compression-Low compression
z
Clogging in intake/exhaust system
Grayish white with all plugs:
z
Air/fuel mixture-Too lean
NOTE:
z
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 and repair procedures. Read the following warnings before
servicing the fuel system:
z
Fuel vapor is hazardous. It can easily ignite, causing serious injury
and damage. Always keep sparks and flames away from fuel.
2007 Mazda CX-9 Grand Touring
2007 ENGINE PERFORMANCE Symptom Troubleshooting (MZI-3.5) - CX-9
Microsoft
Sunday, November 15, 2009 9:27:38 AM
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