Detonation Or Knocking

Check engine oil level.
Check engine for overheating.
Verify base timing is correct.
Check for correct operation of thermostatic air cleaner assembly.
Check for vacuum leaks.
Check EGR system operation.
Check for broken balancer or pulley.
Check for contaminated or poor quality fuel.
Check for carbon build-up in combustion chamber.
Ensure spark plug application is correct.
Check for correct PROM application.