Detonation (Knock)
- Check for overheating problems due to low coolant level, loose water pump belt, restricted air flow to radiator or restricted coolant flow through radiator. Check for inoperative cooling fan circuit. Check ignition timing.
- Check for closed EGR system. Check ESC system for no spark retard. Check fuel pressure using CHART A-7 in this article. Remove combustion chamber carbon build up using chemical remover. Check for correct PROM.
- Check for leaking valve stem oil seals. Check for proper operation of transmission or TCC. Check for incorrect engine basic parts such as cams, heads, pistons, etc. Check for poor fuel quality and proper octane rating.