Mazda 6 Service Manual: No.12 lack/loss of power-acceleration/cruise

No.11 engine stalls/quits, engine runs rough, misses, buck/jerk, hesitation/stumble, surges

No.13 knocking/pinging-acceleration/cruise

Other materials:

Mazda 6 Service Manual: Rocking the Vehicle
WARNING Do not spin the wheels at more than 56 km/h (35 mph), and do not allow anyone to stand behind a wheel when pushing the vehicle: When the vehicle is stuck, spinning the wheels at high speed is dangerous. The spinning tire could overheat and explode. This could cause serious injuries. ...

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 ...