

Diagnostic procedure


Dtc p0301, p0302, p0303, p0304
Dtc p0328Mazda 6 Service Manual: Pcv valve inspection
1. Disconnect the negative battery cable.
2. Remove the intake maniforld.(see INTAKE-AIR SYSTEM REMOVAL/INSTALLATION.)
3. Remove the PCV valve.
4. Blow through the valve and verify that air flows as specified.
If not as specified, replace the PCV valve.
Specification
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Mazda 6 Service Manual: Exhaust system
EXHAUST SYSTEM INSPECTION
Start the engine and inspect each exhaust system component for exhaust gas
leakage.
If leakage is found, repair or replace as necessary.
EXHAUST SYSTEM REMOVAL/INSTALLATION
Warning
When the engine and exhaust system are hot, they can badly burn.
Turn off t ...