For 1990-2009 cars

Cause | Correction
--- | ---
Incorrect oil filter without anti-drainback feature | Install the correct oil filter.
Incorrect oil viscosity |

1. Drain the oil.
2. Install the correct viscosity oil.

High valve lash adjuster leak down rate | Replace the lash adjusters as required.
Worn crankshaft thrust bearing |

1. Inspect the thrust bearing and crankshaft.
2. Repair or replace as required.

Damaged or faulty oil filter by-pass valve |

1. Inspect the oil filter by-pass valve for proper operation.
2. Repair or replace as required.

Malfunctioning camshaft position actuators - improper oil viscosity or contamination. The result is camshaft actuator locking pin does not lock |

1. Verify correct engine oil viscosity by changing the engine oil and filter. Reevaluate the concern.
2. Isolate the noise to a specific camshaft position actuator.
3. Replace the camshaft actuator, oil and filter.