If the selector lever will not move from P using the proper shift procedure, continue to hold down the brake pedal.
1. Remove the shift-lock override cover using a cloth-wrapped flat head screwdriver.
2. Insert a screwdriver and push it down.

3. Press and hold the lock-release button.
4. Move the selector lever.
Take the vehicle to an Authorized Mazda Dealer to have the system checked.
Shift-Lock System
Transaxle RangesMazda 6 Owners 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 Owners Manual: Cylinder head gasket
CYLINDER HEAD GASKET REPLACEMENT
Warning
Fuel vapor is hazardous. It can very easily ignite, causing
serious injury and damage. Always keep sparks and flames away from fuel.
Fuel line spills and leakage are dangerous. Fuel can ignite and
cause serious injuries or death and damage. Fuel ...