Mazda VVT Concern
This bulletin applies to 2014 Mazda3 and 2015 CX-5 and Mazda6 vehicles. Some vehicles may experience a check engine light on with DTCs P0011.00 (electric variable valve timing control system over-advanced) and/or P0012:00 (electric variable valve timing over-retarded) stored in memory.
This concern may be caused by variable valve timing (VVT) actuator spring shaft fatigue. During vehicle use, the spring shaft may fail and cause incorrect VVT operation and check engine light illumination.
Verify that DTCs P0011:00 and/or P0012:00 are stored in memory.
Warm up the engine to normal operating temperature.
Inspect various valve timing performance using M-MDS. Access PIDs VT IN_ACT and VT IN_DES. Run the engine from idle up to 3000 rpm. Repeat this 5 times. If the monitor value of the PID item VT IN_ACT does not conform to the VT IN_DES, replace the electric variable valve timing actuator.