This bulletin applies to 2009-2010 Chevy HHR vehicles. According to GM, “in rare instances” a technician may comment that they hear a short, sharp rattle noise from the front of the engine at start-up. Codes P0011, P0014, P0016 or P0017 may also be set.
If the noise is present and is very short and sharp, in duration of 2 to 5 seconds, this may be an issue with the cam actuators not parking properly. Once the noise is verified as the actuators, they must be replaced. If the cam actuators are replaced, also 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 in the solenoids and actuators, change the oil and engine oil filter. It may be necessary to perform an engine oil and filter change multiple times with a test drive in-between changes. The filter and solenoids can be inspected afterwards to ensure that no additional debris is present.