At the Cancun meeting of the world trade talks in September 2003, a powerful new grouping of developing countries emerged. Led by rapidly growing countries and major exporters like Brazil, China, India, and South Africa, this group has been powerful enough to challenge the EU and the US in trade negotiations.
If the situation is really bad it can even be caused by the rod itself contacting the crankshaft journal (where the bearing has become out of place). The most common cause of rod knock is due to a spun bearing (bearing itself actually spins in the end of the rod so it becomes out of position).
In C.I. engines auto ignition is key to combustion, but if the fuel takes some time to vaporize & prepare for combustion then some fuel is accumulated in chamber when auto-ignition starts at end of compression stroke, which causes a sudden large amount of energy release and abrupt pressure rise, and causes knocking sound.