In General, the combustion process that is problematic is the root of the problem knocking. In some instances, this occurs when a mixture of air and fuel mixture in the engine burn out too early. Irregular explosions posed the problem can lead to damaged piston or other damage on the machine and can shorten the life of the engine.
Usually a mixture of air and fuel that would produce less than optimal air so much that less good for the engine and can cause sound beats.
In some cases, the problems on gasoline can also cause irregular combustion giving rise to the sound of a knock in the engine. This usually occurs because of a problem with gasoline octane number of compression fuel that is not normal before spontaneous ignition.
At the time of this spontaneous ignition occurs normally sound voice also beats that could cause damage to the engine. Gases with a low octane rating are usually best able to withstand the compression that is not normal.
The sound of beats can also occur due to engine overheating. In this case, the mixture of air and fuel could really burn without any mere. However spontaneous explosions can occur when the cooling system engine failed to control the temperature in the combustion chamber. Spontaneous combustion that occurs in such cases is usually referred to by the term Pre-Ignition.
Sometimes the engine noise knocking can also be caused due to problems in addition to the problem of combustion for example is the mechanical problems. The mechanical problems, among others, including defects in the bearing crankshaft, wheel style broke, and the water pump bearing has worn out. Besides, the timing belt tensioned which has a loose, air conditioning compressor problems and issues rotor bearings are used as the alternator could also lead to a knock.