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
A KNOCKING SOUND IN THE ENGINE IS MOST LIKELY CAUSED BY ONE OF THE FOLLOWING. 1. PISTON SLAP: Makes a sharp metallic noise. Idle engine and short out each cylinder plug. The noise will disappear when plug with bad piston is shorted.