For 1990-2009 cars

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 stud, nut, or bolt.

• | Repair or replace as required.

Worn valve rocker arm | Replace the valve rocker arm.
Bent or damaged push rod | Inspect the following components, and replace as required:

• | The valve rocker arm

• | The valve push rod

• | The valve lifter

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.
Worn and/or damaged valve rotators | Replace the valve rotators as required.
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 timing chain tensioner if applicable | Replace the timing chain tensioners as required.
Worn engine camshaft lobes |

• | Inspect the engine camshaft lobes.

• | Replace the camshaft and valve lifters as required.

Damaged, broken, or dirty, balance shaft sprocket teeth if applicable | Inspect the following components, and repair as required:

• | The balance shaft gear

• | The camshaft gear

• | The balance shaft rear bushing

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