Owners of 2010-2018 Chevy Camaros may experience an SES light on, and engine misfire and/or a chirp, squeak or tick engine noise. If the SES light is on, the technician will find a P0300-P0308 DTC with misfires counting on a single cylinder that may or may not be felt. This may occur consistently or intermittently.

If a noise is verified, it will not be eliminated by cancelling fuel injectors, and the noise will occur at camshaft speed (half of crankshaft speed). While the cause may be a broken valve spring, a worn camshaft lobe and/or lifter roller or a sticking valve, check for a malfunctioning AFM lifter (active fuel management). 

On engines equipped with AFM, you can command AFM on with the scan tool which will unlatch the lifters on cylinders 1, 4, 6 and 7 and stop opening the related valves.

If the noise is eliminated, there is a good chance that the noise is coming from the valvetrain of cylinders 1, 4, 6 or 7. If an AFM lifter unlocks as soon as the engine is started, an SES light and DTC P0300 will be experienced with engine misfires on cylinder 1, 4, 6 or 7, but it is unlikely that any noise will be heard.

If an AFM lifter is mechanically stuck/stuck, a consistent valvetrain tick noise, SES light and DTC P0300 will be found.

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