Diagnostic procedure

WARNING: This page is about a different car, the 2009 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

STEP	INSPECTION	RESULTS	ACTION
1	Remove and shake the PCV valve Does the PCV valve rattle?	Yes	Go to the next step.
1	Remove and shake the PCV valve Does the PCV valve rattle?	No	Replace the PCV valve (See PURGE SOLENOID VALVE REMOVAL/INSTALLATION [L5] .)
2	Inspect for the following External leakage Proper dipstick Proper engine oil viscosity Are all the items normal?	Yes	Inspect the internal engine parts such as valves, valve guides, valve stem seals, cylinder head drain passage, and piston rings
2		No	Service if necessary. Repeat Step 2
3	Verify test results If normal, return to the diagnostic index to service any additional symptoms (See SYMPTOM DIAGNOSTIC INDEX [L5] ) If the malfunction remains, inspect the related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis. If the vehicle is repaired, troubleshooting is completed. If the vehicle is not repaired or additional diagnostic information is not available, reprogram the PCM if a later calibration is available. Retest