NO.29 SPARK PLUG CONDITION [LF]
POSSIBLE CAUSE & DESCRIPTION (SPARK PLUG CONDITION)
Replace the non-
return valve.
3
Verify test results.
If normal, return to diagnostic index to service any additional
symptoms.
(See
ENGINE SYMPTOM TROUBLESHOOTING [LF]
.)
If malfunction remains, inspect related Service Bulletins and/or
On-line Repair Information and perform repair or diagnosis.
If vehicle is repaired, troubleshooting completed.
If vehicle is not repaired or additional diagnostic
information is not available, replace the PCM.
(See
PCM REMOVAL/INSTALLATION [LF]
.)
29
SPARK PLUG CONDITION
DESCRIPTION
Incorrect spark plug condition
Wet/carbon stuck on specific plug:
Spark-Weak, not visible
Air/fuel mixture-Excessive fuel injection
volume
Compression-No compression, low
compression
Malfunction spark plug
Grayish white with specific plug:
Air/fuel mixture-Insufficient fuel injection
volume
Malfunction spark plug
Wet/carbon is stuck on all plugs:
NOTE:
Inspecting spark plugs condition can
determine whether problem is related to a
specific cylinder or possibly all cylinders.
2007 Mazda MX-5 Miata Sport
2007 ENGINE PERFORMANCE Symptom Troubleshooting - MX-5 Miata
Microsoft
Thursday, July 09, 2009 2:42:11 PM
Page 113
© 2005 Mitchell Repair Information Company, LLC.
