Diagnostic procedure
Mazda 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: Emission Control System
This vehicle is equipped with an emission control system (the catalytic converter
is part of this system) that enables the vehicle to comply with existing exhaust
emissions requirements.
WARNING
Never park over or near anything flammable: Parking over or near
anything flammable, such as dry ...