Symptom Diagnosis: Detonation/Knocking

Check engine oil level.
Check engine for overheating.
Verify base timing is correct.
Check for vacuum leaks.
Check EGR system operation (if equipped).
Check for contaminated or poor quality fuel.
Check for carbon build-up in combustion chamber.
Ensure spark plug application is correct.
Check for correct torque of knock sensor (if equipped).
Check for correct knock sensor signal (if equipped).
Ensure ECU application is correct.