Engine knock is one of the most annoying problems a vehicle can have, but not many know what it is or how it is caused. Basically, engine knock (also known as pinging, detonation, and sparking) occurs when the air / fuel mixture in a cylinder is incorrect, causing the fuel to burn unevenly. Under normal conditions, the fuel burns in pockets and not in a huge fireball. When each fuel bottle burns, it will be shocked, burning the next until all of the fuel in that blow is burned. When a
shock occurs, the pockets do not burn evenly and cause shock waves at the wrong time, which can damage the cylinder wall and the piston itself. This also creates the usual "ping noise," which is often described when knocking occurs.

The 3 most common engine problems >>
The blow of the engine can be caused by many things. However, some of the most
common problems are stated below:

The fuel in your car has an octane rating that is too low:- The octane number of gasoline is sometimes known as AKI: Anti Knock index. Manufacturers recommend a certain rating to maintain optimal performance in their vehicles. If you use a gas that has an AKI that is too low, you can use an octane propellant, purchased at any auto parts store, to bring it to levels that allow normal operation. If you use the correct classification and still have problems, try a different brand of gasoline. The use of a gasoline with an AKI higher than that recommended by the manufacturer will not have any adverse effect.

What is the best gas octane rating?
The octane of the gas is the tendency of the fuel to burn and is achieved by mixing the fuel with additives. A higher octane rating means that the fuel will burn slowly, while fuels with lower octane numbers will burn faster. High performance vehicles, such as race cars, will require high octane fuel such as premium gas. This is not necessary for other cars, and the use of low octane fuel, such as regular gas, should be fine. However, if you drive a car with a carburetor, you must consider the higher octane fuel, since the carburetor is not as efficient as the new fuel injection technologies. Therefore, you can conclude that the best fuel classification for your vehicle is indicated in the owner's manual, which is 87 for most cars

Carbon deposits in cylinder walls: - When deposits form, the volume of the cylinder effectively decreases, which increases the compression that can cause bumps. To combat this, first try to buy some detergent additive in an auto parts store, and then try to change the fuels. If your car is prone to hitting, you may want to add the detergent at each filling.

Your vehicle has incorrect spark plugs: - Manufacturers have recommended spark plugs for each vehicle and often list some alternatives. If your car works with something other than what is suggested, you may have to call. The heat range of a spark plug is often in its part number, and the spark plug is designed to work in that range. His work, besides producing sparks, is also extracting the heat from the combustion chamber and placing it on the head. Try changing your plugs if altering your fuel does not help.

The three causes of detonation are the most common and also the least expensive to solve. If your car still experiences detonation after following these suggestions, try taking it to an accredited store.

Source:
http://www.eliancars.com/2019/01/3-major-causes-of-engine-knock.html#more
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