The knocking is creating the rattling sound that heard from some of the engines when they drive at low velocity in a high gear. The knocking or the pinging noise is caused by the cylinder walls that vibrates into the intense pressure waves that will build up. This happens due to the auto ignition of the unburnt part of the fuel and air mixture that has remained inside the cylinder. The knocking will increase when the ignition time is advanced or when spark fire in the plug easiest rather than the later. It occurs when the piston is in the motion and raises due to the compression temperatures and pressures in the earlier mentioned unburnted gases to the point where the auto- igniteses. It is a common problem in many Indian cars because of the poor quality and low octane fuel. It is less resistance to knocking. In the normal condition the air fuel mixture will ignited by the sparks from the spark plug. The spark plug initiates the burning of the compressed fuel and air mixture that ignited advance allows them to combustion happen in the pressure peak. This squeezing works for the maximum from the expansion of the gases. It is an abnormal condition that does not happen. The air-fuel across the boundary of ignition, traps the heat and get ignited from the abnormal way. This provides the abnormal ignition with the explosive sound called as knocking. It is an indication that the abnormal burning of the fuel and air mixture. The knocking has the potential of affecting the engine more adversely. If you allow them to happen for a long period. This can cause the mechanical damage of the engine, overheating of the engines and the abrasion in the piston, which reduce the engine life span. There are two types of knocking can be classified as: 1) pre-ignition and 2) detonation. Detonation occurs during the ignition time. The sparkling plug ignites the fuel and air mixture that flames move toward downwards rapidly to burn the mixture. This process takes some of the seconds only. However, at this time the last part of the fuel and air mixture explodes before the flames from the front reaching for it. It is an unwanted explosion due to the combination of combustion temperature, pressure and the antiknock quality of the fuel. It is the uncontrolled explosion works against the normal combustion and creates the detonation. The prevention is the happen before the time of ignition, it compressed the fuel-air mixture ignites before the spark fire the plug reaching for it. It is usually because of the deposition in the combination of the chambers that get hotter than the temperature in the ignition of the mixture in the cylinder. It can happen when the combustion chambers, pressure and temperature exceeds the knock resistance of the fuel. You can prevent the knocking by simply following the minutes of knocking that can be minimized if one take care about the following measures which is: 1] use higher octane fuel in the vehicles. This will ensure you of high bearing temperature of the fuel and reduce the knocking. 2] Reduction of the extra and avoiding the load on the engine will help to minimize the knocking. 3] Do not allow the much pressure for raising two above a certain limit while driving in a happy rev-range. Do not force the RPM rise in lower the gear? This will ensure you to reduce the peak pressure inside the cylinders. In addition, 4] the addition of some of the antiknock additives will help you in reducing the knocking. Hence, these should used after you properly guided and consultations. It causes owing to following thing: one] the carbon deposited because of the heat is the fence and be able to contribute the factor of the pre-ignition. An overhead sparkling plug will too the hot warmth range for the submission. The glowing carbon deposited in a hot tire out valve. It will mean the valve is organization too hot causes of its poor seating and a feeble valve spring. 2] It has the edge sharper in the burning chambers of the piston that are rounded with the gear eliminate causes. 3] The sharp edges of the valve will grounded improperly, but it wills not enough for the edge left on the boundaries. 4] The mixture of the lean fuel. 5] It is the engine is hotter than a normal cooling organization problem that less coolant level, slip the fan grasp, out of action electric cooling the fan and other system problem of cooling. 5] The auto-detonation of the engine will create the oil droplets. Remove the inadequate oil in the steam engine. It wills due to large the variation in the fuel quality. It is a great figure of engines that contain the mechanisms to notice the knocking and regulate the time and the boosting pressure accordingly. It improved the performance of far above the ground-octane fuels while plummeting the risk of the engine damage causes by the knock running on the less octane fuel. It the example of the turbo charged engines, Saab that where the system called the routine performance manage which used as to reduce the pressure caused by the engines to knock. It has the a variety of monitoring plans for the commonly utilizes by the tuner as a method of considering the listen to the engine in arranging to tune the certain vehicles for safety and load the return vehicle safely. Under the ideal condition, there is a common internal combustion engine, which burns the air and fuel in the cylinder in order to control the fashion. The combustion started by just the spark plugging some 10 to 40 crankshaft degrees from the top of the dead center. It will depend on many factors to involve the engine speed and load. The ignition is an advance and allows the time for the combustion process for increasing on to peak pressure at the time for the maximum recovery of the work that has expanded the gases. The spark across the sparking plug electrodes creates the small kernel frame that will approximately the size of the plug gap. It can grow in size as well as heat output increases.