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.
Internal Mechanical Problems. 1  Internal mechanical problems can also cause engine knocking. One such problem stems from excessive clearance inside the bearings in the connecting rods that transfer the downward movement of the pistons to crankshaft rotation. Each time the piston changes direction, there is a knock from the metal hitting metal. This is often referred to as a rod knock. It is usually very rhythmicâit increases with engine speed and intensifies with engine load. Other mechanical problems that lead to engine knocking are: Defective main crankshaft bearings
3 Causes of Engine Knock. Engine knock is among the most disturbing problems a vehicle can have, but not many people know what it is, or how it is caused. Basically, engine knock (also known as pinging, detonation and spark knock) occurs when the air/fuel mixture inside a cylinder is incorrect, which makes the fuel burn unevenly.