Operation CHARM: Car repair manuals for everyone.

Detonation/Spark Knock/Pings


1. Inspect cooling system for conditions causing overheating.
2. Check operation of electric engine cooling fan, if equipped.
3. Check base ignition timing.
4. Test EST and ESC systems.
5. Inspect EGR valve and check EGR control system for conditions causing valve not to open.
6. Check TCC system operation, ensuring clutch does not engage prematurely or fail to disengage.