Knock sensor error codes P0325, P0326, P0327, P0328

How does the sensor work and why is it needed?

The operation of the mechanism is based on the principle of a piezoelectric element.
This means that if vibration of a different nature occurs in the engine cylinder, a signal will be transmitted to the ECU using electronic pulses. In turn, the final element in this chain will make changes to the operation of the ignition angle. This algorithm of actions allows you to protect components and parts from mechanical damage. On the “fourteenth” in most cases there are broadband mechanisms, but often the manufacturer also installed a resonant type of device, most often on the very first copies of the VAZ-2114

The broadband mechanism is superior to its counterpart in that it has a wider range of capabilities. Such a sensor is capable of capturing noise of various frequencies, which undoubtedly gives the vehicle system additional stability.

The devices operate on different principles, therefore, if the resonant sensor breaks down, it cannot be replaced with a broadband one. The situation is similar in the opposite case. If there is an urgent need to replace or change the operating principle of the mechanism, you will have to purchase a new control unit.

What does knock sensor error P0326 mean, why does it appear and how to fix it

The ECU, that is, the electronic control unit, constantly receives signals from sensors and sends commands to actuators based on the information received.

If any problems or malfunctions occur, the unit may display this as an error. Speaking of detonation, 4 errors can be recorded here. These codes range from P0325 to P0328. Error P0326 is considered one of the most interesting problems for motorists.

It means, literally translated from English, that the signal from the knock sensor has gone beyond its permissible range. In many ways, this is similar to error code P0325, but there are some peculiarities that are worth paying attention to.

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Bug Prone Cars

It is difficult to identify specific models that may encounter a similar problem with the knock sensor.

This is a problem typical for domestic and imported cars. Therefore, you can encounter error 0326 on the VAZ 2114, Hyundai Accent, other VAZ representatives, including 2115, models such as Kalina, Priora, etc.

It would be wrong to say that on the same VAZ 2114, error type P0326 occurs more often than on Kia Rio or Renault Logan cars.

The only thing worth adding is that this error most often occurs on vehicles that initially use low-quality sensors.

One of the causes of errors on the part of the knock sensor is refueling with fuel with a lower octane number than recommended by the manufacturer.

Therefore, it is impossible to attribute this error to some cars as chronic and often occurring. Certain conditions must simply be created for its occurrence. And it’s not always the motorist’s fault. If the car comes with a bad sensor from the factory, then there is a high risk that the engine check light will soon light up on the dashboard, and the corresponding code will be recorded in the control unit.

Determining and decoding errors on the VAZ 2114

Error p0171

Self-diagnosis of a car allows you to identify faults, but some of them are rarely identified. An odometer is used for diagnostics.

Self-diagnosis of VAZ 2114

The sequence of actions is as follows:

1. Press and hold the odometer button and turn the ignition key to the first position.
2. Release the odometer button and press briefly again. As a result, the firmware version will be displayed.
3. Now, to see the error codes, you need to press and release the odometer button again.

Error codes are in the form of numbers from 1 to 9 and two-digit numbers, unlike those displayed by the on-board computer. Thus, you can use the odometer to identify some car faults. The most common errors are shown in the table below.

Diagnosis of faults using special equipment

To identify faults, service stations usually use the car’s on-board computer and a laptop with specialized applications. In this case, it is possible to obtain error codes that correspond to various problems. The most common of them are shown in the table.

If errors occur with other codes, you should read the information about them in the file that comes with the car diagnostic application, or search on the Internet.

The controller clears the memory after turning off the engine with the ignition and disconnecting power from the battery for 10-15 seconds. In this way, you can determine after repair whether the malfunction has been eliminated.

Errors in the VAZ 2114 occur quite often, so the ability to recognize them will not be superfluous to carry out proper car repairs. For correct diagnosis, you will need a computer with a special program and an understanding of the on-board computer readings.

Error Diagnosis Methods

In 2022, errors on the VAZ 2110 on-board computer can be identified in two ways.

Self-diagnosis VAZ 2110: error codes

To enable self-diagnosis mode, the driver or technician will need to perform a certain sequence of actions.

If everything is done correctly, one of the following symbols will light up on the device:

Also, error 14 VAZ 2110 or another two-digit number will indicate the presence of two problems. Usually, with such a picture, the ciphers are summed up. For example, error 10 VAZ 2110 may indicate problems in circuits No. 4 and 6.

How to reset errors on a VAZ 2110

Typically, the procedure is carried out after repairing the unit for which the fault code is responsible. In this case, the symbol does not disappear - it must be forcibly reset. This is done quite simply. The user is required to enter the service mode (hold down the daily mileage button), then double-click on any control. After completing the manipulations, a code will appear on the display. To eliminate this, the daily mileage button is pressed for 3-4 seconds and the system is reset. The machine exits the dialog box automatically after 30 seconds of inactivity.

Error P0325

DmitryCorsten Blog Error codes for on-board computers of the Samara-2 family VAZ 2113, VAZ 2114, VAZ 2115

Error code P0325 has an official name - “malfunction in the knock sensor circuit.” In English it sounds like: Knock Sensor 1 Circuit Malfunction. It signals to the driver that the engine control unit does not receive a signal from the DD. Due to the fact that some problems have arisen in its power supply or signal circuit. The cause of this error may be very low or very high voltage coming from the sensor due to a break or poor contact in the wiring harness block.

Possible causes of the error

There are several reasons why error p0325 may occur. Among them:

• broken knock sensor wiring;
• short circuit in the DD wiring circuit;
• malfunction in the connector (chip) and/or contact DD;
• high level of interference from the ignition system;
• malfunction of the knock sensor itself;
• malfunction of the engine control unit (abbreviated as ECM).

Conditions for recording error code 0325

The code is installed in the ECU memory on a warm engine at a crankshaft speed of 1600-5000 rpm. if the problem does not go away within 5 seconds. and more. The archive of fault error codes itself is cleared after 40 consecutive cycles without fixing a fault.

To find out exactly what problem caused the error, additional diagnostics must be performed.

External symptoms of error P0325

External signs of this error may include the following situations. However, they can also indicate other errors, so you should always perform additional diagnostics using an electronic scanner.

• The Check Engine light on the dashboard is activated;
• the engine control unit operates in emergency mode;
• in some cases, engine detonation is possible;
• loss of engine power is possible (the car “does not pull”, loses its dynamic characteristics, accelerates poorly);
• Unstable engine operation at idle.

In general, the symptoms of failure of the knock sensor or its wiring are outwardly similar to those when the ignition is set late in the car (on carburetor engines).

Error diagnosis algorithm

To diagnose error p0325, it is necessary to have an electronic error scanner (for example ELM 327 OBD-II). The error detection algorithm will be as follows:

• First, you need to make sure that the alarm was not false. To do this, you need to reset the error using the scanner (if there are no others, otherwise you need to deal with them first) and perform a test drive. If error p0325 occurs again, then we continue further.
• You need to check the functionality of the knock sensor. This can be done in two ways - using a multimeter and mechanically. Using a multimeter, you first need to measure the voltage of the sensor when pressure is applied to it. And also check its circuit to the ECU for an open circuit. The second, simpler method is to simply hit the engine at idle speed in the immediate vicinity of the sensor. If it is working properly, then the engine speed will drop (the electronics will automatically change the ignition angle), which is true that this algorithm does not work on all cars and in some cases, reading the BC signal from the DD works under other additional conditions).
• Check ECM functionality. In rare cases, the program may crash. It is unlikely that you will be able to perform the check yourself, so it is better to seek help from an official dealer of your car manufacturer.

How to get rid of error p0325

Depending on what exactly caused the p0325 error, several options are possible to solve this problem. Among them:

• cleaning contacts or replacing wiring connectors (chips);
• repair or replacement of wiring from the knock sensor to the engine control unit;
• replacing the knock sensor itself, most often this is what is done (this unit cannot be repaired);
• flashing or replacing the engine control unit.

Error p0325 itself is not critical, and the car can get to a car service center or garage under its own power. However, there is a risk that if detonation occurs in the engine, the ECU will not be able to react properly and eliminate it. And since detonation is very dangerous for the power unit, you need to get rid of the error and carry out the appropriate repair work as quickly as possible after its occurrence.

Symptoms of malfunction

The main driver symptom of P0328 is the MIL (Malfunction Indicator Light). It is also called Check engine or simply “check light”.

They can also appear as:

1. The “Check engine” warning light on the control panel will light up (the code will be stored in memory as a malfunction).
2. The motor can operate, but with reduced performance (drop in power).
3. Jerking and detonation in the engine.
4. Increased fuel consumption.
5. There may be no symptoms other than a stored DTC.

Error P0328 is not considered very serious. When it appears, serious problems with the car's handling are unlikely to arise, but a slight drop in engine power is possible.

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Troubleshooting

To get rid of the error that has arisen, which was considered, it is first necessary to eliminate the provoking factors.

To do this, as part of the diagnostics, the reasons why the corresponding code was written into the ECU memory are determined, and the control unit activated the engine check light on the dashboard.

If you eliminate the cause, but do not reset the error itself, the sensor will continue to work incorrectly, since the ECU perceives it as faulty.

That is, the first step is to eliminate the cause, after which the error itself is erased from the block. The easiest way to do this is to reset the negative terminal from the battery. But, depending on the specific car, the manufacturer provides a certain algorithm and method for resetting errors. To do this, you should look at the instruction manual.

Most often, there is no need to connect scanners and use additional equipment. The error is erased by pressing the appropriate keys or by performing certain actions in the prescribed order.

Source

How to replace the sensor

Replacing the mechanism yourself is not difficult. It is located between the second and third cylinders; you need to open the hood and provide yourself with unhindered access

It is important that the engine is turned off at this time. As soon as the DD is detected, it is necessary to disconnect the plug going to the sensor wires

If the mechanism is broadband, then to complete all the work you will need a key set to “13”. In the case of a resonant device, you should arm yourself with a key set to “22”. You just need to unscrew the nuts from the stud with a “13” wrench or the piezoelectric sensor itself with a “22” wrench. It is also necessary to clean the contacts with sandpaper to remove all dirt and oxidation. This procedure should not be neglected, because the quality of the transmitted signal depends on the state of the contacts.

Oxidation and various types of plaque interfere with the transmission of a high-quality signal. As a consequence, this leads to a decrease in the level and accuracy of the impulse, which will leave its mark on the operation of the car. After which it is necessary to install a new mechanism and reassemble in the reverse order.

What it is

The first step is to understand the meaning of error code P0326 and what the entry of such a value in the control unit indicates.

The error in question indicates that during the sensor check, a malfunction in the form of a short circuit or break was detected on the ECU side. The controller has failed.

If the difference between the signal from the knock controller and the noise level generated is lower than the threshold value recorded over a period of time, the ECU generates an appropriate error.

Also, a similar code may appear if the sensor signal parameters are lower or higher than the level within which it should operate.

Error p0328

Error code P0328 by definition means that “the output voltage of the knock sensor is above the threshold value” (usually the threshold value is 4.5 V). In English it is called Knock Sensor 1 Circuit High. This error is similar to the previous one, but the difference is that in this case it may be caused by a break in the signal/power wires between the knock sensor and the electronic control unit or a short circuit of the wiring section to the ECU to “+”. Determining the cause is made difficult by the fact that such an error occurs much more often not because of problems with the chain, but because of poor fuel flow into the combustion chamber (lean mixture), which occurs due to clogged injectors, poor operation of the fuel pump, low-quality gasoline or phase shift and installation early ignition.

External signs

Indirect signs by which it can be judged that error p0328 is occurring are similar to those described above. In particular, the Check Engine light on the dashboard is activated, the car loses its dynamics and accelerates poorly. In some cases, increased fuel consumption is observed. However, the listed signs may indicate other malfunctions, so mandatory computer diagnostics are needed.

The cause must be looked for by studying the symptoms, and the search itself must be done by removing the connector for connecting the knock sensor with the engine running. It is necessary to measure the reading parameters and observe the behavior of the motor.

Causes of error p0328

The causes of error p0328 may be the following malfunctions:

• Damage to the knock sensor connector or significant contamination (ingress of debris, engine oil);
• the circuit of the mentioned sensor has a short circuit or open circuit;
• the knock sensor itself is faulty;
• there is electrical noise in the sensor circuit (interference);
• low pressure in the vehicle fuel line (below the threshold value);
• use of fuel that is unsuitable for the vehicle (low octane number) or its low quality;
• error in the operation of the electronic engine control system (failure).

Another interesting reason noted by car enthusiasts is that a similar error can appear if the valves are incorrectly adjusted, in particular, they have too much clearance.

Possible troubleshooting options

Depending on what caused the p0328 error, the ways to eliminate it will be different. However, the repair procedures are completely similar to those described above, so we’ll simply list them:

• check the knock sensor, its internal resistance, as well as the voltage it outputs to the computer;
• make an audit of the wires connecting the electronic unit and the DD;
• perform an audit of the chip where the sensor is connected, the quality and reliability of the contacts;
• Check the torque value at the knock sensor seat and, if necessary, set the desired value using a torque wrench.

As you can see, the verification procedures and reasons why errors p0325, p0326, p0327 and p0328 appear are largely similar. Accordingly, the methods for solving them are identical.

Remember that after eliminating all faults, you must erase error codes from the memory of the electronic control unit. This can be done either using software (preferably), or simply by disconnecting the negative terminal from the battery for 10 seconds.

How to Troubleshoot or Reset Trouble Code P0328

Some suggested steps to troubleshoot and fix error code P0328:

1. Visually inspect the electrical wires and connectors leading to the sensor.
2. Check the continuity of the wiring from the PCM to the knock sensor wiring connector.
3. Measure the resistance of the knock sensor and compare with factory specifications.
4. If necessary, replace the knock sensor.

Please note that there are two types of knock sensors, resonant in the form of a barrel and broadband in the form of a ring-washer.

What you need to know about the phase sensor

So, what is a VAZ 2114 phase sensor, how to find it and what are its signs of malfunction?

Device and purpose

DF installation location

DF is a regulator necessary to obtain data on the functioning of the vehicle engine and transmit this information to the ECU. As for the design, the DF consists of a sensitive component as well as a pulse converter. The design of the latter, in turn, includes an operational amplifier, an output stage, and a bridge circuit.

The sensing component located inside the structure operates on the principle of a Hall regulator. Its purpose is to transmit an impulse at the moment when a magnetically conductive component is located next to the microcircuit. As for the location of the VAZ phase sensor, it is located on the side of the cylinder block, next to the air filter element.

Malfunctions

A device failure can be identified by certain signs:

• increased gasoline consumption;
• malfunctions in the machine’s self-diagnosis;
• decreased dynamics when accelerating a car;
• Errors 0343, 0340 or a Check lamp may appear on the control panel.

The light bulb Check usually appears if the DF is inoperative.

How to connect DF correctly

Check and replacement

To check on an eight-valve engine, you must perform the following steps:

1. At the multimeter terminal V1, you need to set the voltage to 13.5 volts; this probe is connected to pin E. At the second pin, which is connected to pin B, you need to set the voltage to 0.9 volts.
2. After closing the contacts, a screwdriver or plastic steel should be brought to the end of the regulator. And if the DF is functioning properly, the voltage at output B should drop to 0.4 volts. If the readings differ, then the DF should be replaced (the author of the video is In Sandro’s garage).

As for the sixteen-valve engine, the principle is slightly different:

1. The multimeter is set to operating mode V2, the voltage at output E should be set to 13.5 volts, and at output B to 0.4 volts.
2. We again bring a screwdriver or plate to the DF body. If the DF is working normally, the voltage level will increase to 0.9 volts

To perform a replacement, you need to do the following:

1. First you need to turn off the battery by removing the terminal from it.
2. Using a 10mm ratchet wrench, unscrew the screw securing the device to the cylinder block. Disconnect the wires that are connected to the DF.
3. Remove the DF and replace it with a new one. It is a good idea to clean the pad contacts from dirt or oxidation.

ERRORS ON-BOARD COMPUTER KALINA/PRIOR

0102 Low level of mass air flow sensor signal 0103 High level of mass air flow sensor signal 0112 Low level of intake air temperature sensor 0113 High level of intake air temperature sensor 0115 Incorrect signal of coolant temperature sensor 0116 Incorrect signal of coolant temperature sensor 0117 Low level of temperature sensor coolant 0118 Coolant temperature sensor signal high 0122 Throttle position sensor signal low 0123 sensor signal high 0130 Oxygen sensor signal 1 incorrect 0131 Oxygen sensor signal low 1 0132 Crankshaft sensor signal high 1 0133 Slow response oxygen sensor 1 0134 No signal from oxygen sensor 1 0135 Malfunction of oxygen sensor 1 heater 0136 Short circuit to ground of oxygen sensor 2 0137 Low level of oxygen sensor 2 0138 High level of high signal of oxygen sensor 2 0140 Open circuit of oxygen sensor 2 0141 Malfunction of oxygen sensor 2 heater 0171 Too lean mixture 0172 Mixture too rich 0201 1 control circuit open 0202 Injector 2 control circuit open 0203 0204 Injector 4 control circuit open 0261 Injector 1 circuit short to ground 0264 Injector 2 circuit short to ground 0267 Injector circuit short to ground sunki 3 0270 Short to ground in the injector 4 circuit 0262 Short to +12V in the injector 1 circuit 0265 Short to +12V in the injector 2 circuit 0268 Short to +12V in the injector 3 circuit 0271 Short to +12V in the injector 4 0300 Many misfires 0301 Misfires in 1 cylinder 0302 Misfire in cylinder 2 0303 Misfire in cylinder 3 0304 Misfire in cylinder 4 0325 Knock sensor circuit open 0327 Knock sensor signal low 0328 Knock sensor signal high 0335 Crankshaft position sensor signal 0336 Crankshaft position sensor signal 0340 Sensor error and phases 0342 Low phase sensor signal 0343 High phase sensor signal 0422 Low converter efficiency 0443 Canister purge valve circuit malfunction 0444 Short or open canister purge valve 0445 Short to ground canister purge valve 0480 Cooling fan circuit malfunction 1 0500 Incorrect Speed ​​sensor signal 0501 Invalid signal speed sensor 0503 Speed ​​sensor signal interruption 0505 Idle speed controller error 0506 Low idle speed 0507 High idle speed 0560 Incorrect on-board network voltage 0562 Low on-board network voltage 0563 High on-board network voltage 0601 ROM error 0603 External RAM error 0604 O Internal RAM error 0607 Malfunction knock channel 1102 Low oxygen sensor heater resistance 1115 Faulty oxygen sensor heating circuit 1123 Rich idle 1124 Lean idle 1127 Rich partial load 1128 Lean partial load 1135 Oxygen sensor heater circuit 1 open, short circuit 1136 Rich mixture in Light Load mode 1137 Lean mixture in Light Load mode 1140 Measured load differs from calculation 1171 Low CO potentiometer level 1172 High CO potentiometer level 1386 Knock channel test error 1410 Canister purge valve control circuit short circuit to +12V 14 25 Chain control circuit of the canister purge valve, short circuit to ground 1426 Control circuit of the canister purge valve open 1500 Open circuit of the fuel pump relay control circuit 1501 Short circuit to ground of the fuel pump relay control circuit 1502 Short circuit to +12V of the fuel pump relay control circuit 1509 Overload of the idle speed regulator control circuit 1513 Idle air regulator circuit really speed short circuit to ground 1514 Idle speed control circuit short circuit to +12V, open 1541 Fuel pump relay control circuit open 1570 Incorrect APS signal 1600 No communication with APS 1602 Loss of on-board power supply voltage to the ECU 1603 EEPROM error 1606 Rough road sensor incorrect signal 161 6 Sensor rough road low signal 1612 ECU reset error 1617 Rough road sensor high signal 1620 RFOM error 1621 RAM error 1622 EPROM error 1640 EEPROM Test error 1689 Incorrect error codes 0337 Crankshaft position sensor, short to ground 0338 Crankshaft position sensor, short to ground open circuit 0441 Air flow through valve incorrect 0481 Cooling fan circuit malfunction 2 0615 Starter relay circuit open 0616 Starter relay circuit short circuit to ground 0617 Starter relay circuit short circuit to +12V 1141 Oxygen sensor 1 heater malfunction after the neutralizer 230 Fuel pump relay circuit malfunction 263 Force driver malfunction nki 1 266 Malfunction Injector Driver 2 269 Injector Driver 3 Malfunction 272 Injector Driver 4 650 CheckEngine Lamp Circuit Malfunction

Nuances of self-diagnosis of the VAZ 2114

When carrying out diagnostics at specialized service stations or independently, various results and error codes can be obtained. Not all drivers know that faults can be identified without an on-board computer. An odometer is used for this. A significant drawback of such diagnostics is the addition of error numbers into a single sum. For example, if an error of 8 and 1 occurs, the odometer will display the number 9. The device's memory is not automatically cleared, so error codes will be displayed until manually reset by disconnecting the battery terminals for a few seconds.

Resetting the "checkengine" error

As you can see from the video, the error can be reset by following these steps:

• Turn off the engine, but leave the car's ignition on.
• Disconnect the car battery terminal and wait a few seconds.
• Reinstall the terminal and start the engine.

The error will be reset after these steps, but if it is caused by serious malfunctions in the engine, it will occur again. In this case, the best option would be to contact a service station.

Conditions for the error

Before the error in question is recorded in the electronic unit, certain conditions must be met. Namely:

• The ECU must constantly operate in the normal mode to control fuel detonation processes. Most often, this mode is active by default, so no additional steps need to be taken to switch to it.
• Based on the information received from the sensor, it was found that the amplitude of the signal transmitted to the ECU is lower than the minimum calculated threshold value established by the manufacturer.
• In parallel with this, the engine has already warmed up; it operates at a speed of 2500 rotations per minute, or higher.

The presented conditions must be recorded 3 times. Only after 3 repetitions does the error appear.

The problem arises for a reason. Its appearance may be due to several reasons.

Knock sensor error (codes P0325, P0326, P0327, P0328)

A detonation error can be caused by various reasons - a low or very high signal from it to the electronic engine control unit (ECU), a circuit error, an out-of-range voltage or signal range, as well as a complete failure of the knock sensor (hereinafter referred to as DS), which happens very rarely. However, in any case, the Check Engine light on the car’s dashboard is activated, symbolizing the occurrence of a malfunction, and when the engine is running, there is a deterioration in dynamics, dips in speed and an increase in fuel consumption. Often, “dzhekichana” can be detected as a result of using bad fuel, but often it’s all about the contact and wiring of the motor. The error code can be easily read using diagnostic scanners. For an explanation of all knock sensor errors, indicating the causes and methods for eliminating them, see below.

There are actually four knock sensor errors - P0325, P0326, P0327 and P0328. However, the conditions for their formation, external signs, and methods of elimination are very similar, and sometimes identical. These diagnostic codes cannot specifically report the cause of the failure, but they can point you in the direction of troubleshooting the knock sensor circuit. Quite often, this is a bad contact in connecting the sensor to the connector or in the contact of its surface to the engine, but sometimes the sensor really fails (cannot be repaired, only replacement is possible). Therefore, first of all, the operation of the engine knock sensor is checked.

Causes of error P0327

There are several main reasons that lead to error P0327:

The knock sensor is not installed correctly or has defects that prevent it from transmitting information correctly, for example, oxidation of the contacts or poor fastening;

To fix the problem, you need to step by step check the possible faults indicated above.

Error p0326

Error code p0326 during diagnostics is deciphered as “ out of the permissible range of the knock sensor signal .” In the English version, the code description is Knock Sensor 1 Circuit Range/Performance. It is very similar to error p0325 and has similar causes, symptoms and solutions. The electronic control unit detects knock sensor failure due to a short or open circuit by checking that the analog input signal from the sensor is within the required range. If the difference between the signal from the knock sensor and the noise level is less than the threshold value over a certain period of time, then this becomes the reason for the formation of error code p0326. This code is also registered if the signal value from the mentioned sensor is higher or lower than the corresponding permissible values.

Symptoms of error P0327

P0327 has the same symptoms as other knock sensor related errors. That is:

The engine has noticeable problems with dynamics;

• The electronic control unit switches the car into emergency mode. On some engines, this can lead to the fact that the ECU will programmatically block the ability to increase revolutions above 3-5 thousand per minute, or prevent acceleration over 50 kilometers per hour;
• The engine may be unstable at idle. Often the engine starts to stall at idle if you do not maintain speed with the accelerator pedal.

Please note: Many cars in emergency mode begin to emit black smoke from the exhaust pipe due to a suboptimal air-fuel mixture - this can be attributed to another symptom of the P0327 error.

Read also:  Front suspension of the VAZ 2109 - design, repair, common problems

Signs of an error

The error manifests itself when the engine is warm - in order for fuel detonation to occur, the fuel must be warmed up and able to detonate. Problems with the sensor lead to deterioration in vehicle behavior:

• dynamic characteristics deteriorate;
• fuel consumption increases;
• the engine is unstable at idle;
• dips in engine speed appear.

The reason for the deterioration in performance is a command from the electronic control unit to switch to emergency engine operation when the signal from the knock sensor is low. The ECU specifically limits the engine's capabilities to avoid burning out valves and pistons as a result of excessive detonation. On some vehicles, emergency operation may limit the maximum speed to 3-5 thousand rpm and the maximum speed to 50 km/h.