Upper Engine Noise, Regardless of Engine Speed

WARNING: This page is about a different car, the 2007 Hummer H2. However, it is still accessible from the selected car via links, so may be relevant.

Cause	Correction
Low oil pressure	Perform an oil pressure test. Refer to Oil Pressure Diagnosis and Testing . Repair or replace, as required.
Loose and/or worn valve rocker arm attachments	Inspect the valve rocker arm, bolt, and pedestal. Repair or replace, as required.
Worn or damaged valve rocker arm	Inspect the rocker arm for wear or missing needle bearings Replace the valve rocker arms, as required.
Bent or damaged push rod	Inspect the following components and replace, as required: The valve rocker arm The valve push rod The valve lifter The valve lifter guide The piston Inspect the top of the pistons for valve contact. If the top of the piston shows valve contact, replace the piston and pin assembly.
Improper lubrication to the valve rocker arms	Inspect the following components and repair or replace, as required: The valve rocker arm The valve push rod The valve lifter The oil filter bypass valve The oil pump and pump screen The engine block oil galleries
Broken valve spring	Replace the valve spring and spring shim.
Worn or dirty valve lifters	Replace the valve lifters.
Stretched or broken timing chain and/or damaged sprocket teeth	Replace the timing chain and sprockets.
Worn engine camshaft lobes	Inspect the engine camshaft lobes. Replace the camshaft and valve lifters, as required.
Worn valve guides or valve stems	Inspect the following components and repair, as required: The valves The valve guides
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: The valves The valve guides