This bulletin applies to 2009-2010 Chevrolet HHR vehicles, equipped with a 2.0L, 2.2L or 2.4L engine. A short, sharp rattle noise from the front of the engine may be noticed at start-up.
DTCs P0011, P0014, P0016 or P0017 may also set during this condition.
This may be an issue with the cam actuators not parking properly. Once the noise is verified as the actuator, they must be replaced. If the cam actuators are replaced, remove the CMP actuator solenoids to inspect for debris.
If debris is found, clean and inspect for torn or loose screens and replace the solenoids if necessary. If debris is found, the engine oil and filter must be changed as well.