Always remember that by disregarding a malfunction in the car, you, as a rule, contribute to the total wear and tear and destruction of its parts. This can ultimately lead to costly repairs.
Even if you do not understand too deeply the internal structure of the mechanisms of your car, it is in your power to ensure their smooth operation. Who, if not you, in the first place can detect the instability of the functioning of some nodes. Considering that trips with individual malfunctions can have serious consequences, any driver should at least at least know the minimum of the principles of the work of the parts of his car, know their resource, be able to identify and eliminate commonplace problems regardless of the make and model of the car.
Most modern cars work with a mass of sensors, the malfunction of which, in the main, can be established by means of computer diagnostics on service equipment. However, some sensors make themselves felt quite clearly, and with due care of the driver, it will not be difficult to determine which one has failed.
Knocking combustion of the fuel-air mixture
Problems rarely arise with a knock sensor, only in no case should it be ruled out. It serves to control the engine knock level. The fact is that a small part of the fuel-air mixture in the engine cylinders burns precisely with detonation. This happens under the condition that the mixture is somewhat removed from the spark plug and, when heated, burns with the formation of an "explosion". At the same time, there is a characteristic knock in the crank mechanism of the motor, some drivers say that “fingers knock”.
The occurrence of knocking combustion is usually influenced by the chemical composition of gasoline (fuel with a higher octane number is somewhat more resistant to detonation) and the design features of the engine (as a rule, the higher the compression ratio in the cylinders, the higher octane fuel the car needs).
Knock sensor malfunction
The principle of operation of the sensor is that when the above phenomenon occurs, it sends a signal to the engine control unit, which adjusts the ignition settings to eliminate the resulting knock.
In case of failure of the knock sensor, the car has weak acceleration dynamics, the engine is unstable at idle speed, the “Check Engine” signal lights up on the instrument panel. In addition, fuel consumption increases and, as a result, smoky exhausts appear.
Consequences of failure of the knock sensor
With a faulty sensor, the engine continues to work, but the control unit can no longer correctly set the ignition timing. This is fraught with dangerous consequences. During detonation combustion of fuel, high shock loads arise, and the heat transfer of the crank mechanism increases. In general, all this provokes significant wear of engine parts, which means that it increases the likelihood of engine breakdowns. To save the car engine, it is enough to timely identify the problem and replace the knock sensor.