Low oil pressure

Loose and/or worn follower (valve rocker arm)

Improper lubrication to the followers (valve rocker arms)

Inspect the following components, and repair or replace as required:

Broken valve spring

Replace the valve spring.

Worn or dirty SHLAs (valve lifters)

Replace the SHLAs (valve lifters).

Stretched or broken timing chain(s) and/or damaged sprocket teeth

Replace the timing chain(s) and sprockets.

Worn timing chain tensioner(s)

Replace the timing chain tensioner(s) as required.

Worn timing chain shoe(s)

Replace the timing chain shoe(s) as required.

Worn timing chain guide(s)

Replace the timing chain guide(s) as required.

Worn engine camshaft lobes

Worn valve guides or valve stems

Inspect the following components, and repair as required:

Stuck Valves

(Carbon on the valve stem or valve seat may cause the valve to stay open)

Inspect the following components, and repair as required: