Knock sensor on a VAZ 2114 - what are the signs of a malfunction, check

The operation of the VAZ 2114 power unit may be accompanied by the appearance of detonation. It has a bad effect on the engine, creating parasitic vibration and having a destructive effect on the main elements of the internal combustion engine.

Damage and metal fatigue gradually accumulate in the engine, which results in the imminent need for major engine repairs. A combination of electronic control units and DD is working to eliminate detonation. The meter detects the occurrence of non-optimal ignition of the fuel-air mixture, and the main module corrects the spark advance angle.

How does a knock sensor work?

Car engines can use one of two types of knock sensors: resonant and broadband. But since the first type is already outdated and is rare, we will describe the operation of broadband sensors (WS).

The design of a broadband DD is based on a piezoelectric element, which, when subjected to mechanical action (that is, during an explosion, which, in essence, is detonation), supplies a current with a certain voltage to the electronic control unit. The sensor is configured to perceive sound waves in the range from 6 Hz to 15 kHz. The design of the sensor also includes a weighting agent, which enhances the mechanical effect on it by increasing the force, that is, it increases the sound amplitude.

The voltage supplied by the sensor to the ECU through the connector terminals is processed electronically and then a conclusion is made whether there is detonation in the engine, and accordingly, whether the ignition timing needs to be adjusted, which will help eliminate it. That is, the sensor in this case is only a “microphone”.

Design and principle of operation

Principle of operation

As we know, and some only guess, the maximum efficiency of the engine (dynamics, power, fuel consumption) is greatly influenced by the correctly set ignition timing, which, moreover, must optimally adapt to different engine operating modes. Deviations from the optimal ignition timing parameters are as follows:

• A late ignition timing is fraught with deterioration in vehicle dynamics, engine overheating and increased fuel consumption;
• An early ignition timing angle, in turn, manifests itself in the form of microexplosions in the combustion chamber (detonation), which entails a drop in power and increased valve wear (valve burnout).

And in order to eliminate these deviations, the car’s electronic control unit strives to set the ignition timing as large as possible, but at the same time does not allow it to go into the detonation zone, which the knock sensor reports to the controller. The operating principle of this device is based on the piezoelectric effect. The knock sensor is mounted on the engine block.

Replacing the knock sensor VAZ 2110

And since detonation is, in fact, a micro-explosion, when it is present, vibration appears on the engine body, which compresses the piezoelectric plate, as a result of which a potential difference appears at its contacts.

Device

At the moment, the modern automotive industry produces two types of knock sensors - resonant and broadband types.

VAZ knock sensor interchangeability

As you can see in the above photo, each type of sensor has a completely different operating principle:

• A broadband type sensor records and transmits the entire spectrum of noise to the electronic control unit, which, in turn, processes the received signal and independently detects the noise corresponding to detonation.
• The resonant type sensor is tuned to the frequency of micro-explosions, and accordingly sends a signal to the controller only if it is detected.

Attention! Replacing the knock sensor for VAZ 2110, 2112, 2114, 2115 does not accept replacing one type of sensor with another.

The following can be summarized:

• Under conditions when the vehicle is operated under normal conditions (high-quality gasoline, serviceable spark plugs, etc.), the electronic control unit does not use the subsidy sensor circuit and switches the engine to operation in the optimal parameters mode.
• When, for some reason, detonation begins, an impulse from the knock sensor tells the control unit that the ignition timing must be shifted in one direction until the detonation disappears. In this way, the ECU creates optimal operating conditions for the engine under any operating conditions.
• This method of adjusting engine operation is called “closed loop” and is used by the electronic control unit not only when working with the knock sensor, but also in adjusting other important parameters.

Signs of a malfunctioning knock sensor

If the DD fails completely or partially, a malfunction of the knock sensor manifests itself according to one of the symptoms:

• Engine shaking . If the sensor and control system in the engine are working properly, this phenomenon should not occur. By ear, the appearance of detonation can be indirectly determined by the metallic sound emanating from a running engine (knock of fingers). And excessive shaking and jerking during engine operation is the first way to determine a malfunction of the knock sensor.
• Reduced power or “dullness” of the engine, which is manifested by deterioration of acceleration or excessive increase in speed at low speeds. This happens when, with an incorrect DD signal, the ignition angle is spontaneously adjusted.
• Difficulty starting the engine , especially “cold”, that is, at low temperatures after a long period of inactivity (for example, in the morning). Although it is quite possible for the car to behave this way even at warm ambient temperatures.
• Increased fuel consumption . Since the ignition angle is disturbed, the air-fuel mixture does not meet optimal parameters. Accordingly, a situation arises when the engine consumes more gasoline than it needs.
• Fixing knock sensor errors. Usually the reasons for their appearance are the signal from the sensor going beyond the permissible limits, a break in its wiring, or a complete failure of the sensor. The occurrence of errors will be indicated by the Check Engine light on the dashboard.

However, it is worth considering that such symptoms may indicate other engine failures, including other sensors. It is recommended to additionally read the ECU memory for errors that could arise due to incorrect operation of individual sensors.

Knock Sensor Circuit Malfunctions

In order to identify DD faults more accurately, it is advisable to use electronic error scanners for the electronic control unit. Especially if the check indicator light on the dashboard lights up.

Often, error p0325 “Open in the knock sensor circuit” indicates problems in the wiring. This could be a broken wire or, more often, oxidized contacts. It is necessary to perform preventative maintenance on the connectors on the sensor. Sometimes error p0325 occurs because the timing belt slips by 1-2 teeth.

Error P0328 “Knock Sensor High” often indicates a problem with high-voltage wires. In particular, if the insulation on them or the piezoelectric element breaks through. Similarly, this error can also occur due to the fact that the timing belt has jumped a couple of teeth. To diagnose, you need to check the marks on it and the condition of the washers.

Errors p0327 or p0326 are usually formed in the ECU memory due to a low signal from the knock sensor. The reason may be poor contact from it, or weak mechanical contact of the sensor with the cylinder block. To eliminate the error, you can try treating both the mentioned contacts and the sensor itself with WD-40. It is also important to check the sensor mounting torque, as this parameter is critical to its operation.

In general, it can be noted that the symptoms of a malfunction of the knock sensor are very similar to the symptoms characteristic of late ignition because the ECU, for the sake of safety for the engine, tries to automatically do it as late as possible, since this prevents destruction of the engine (if the angle is too early, then in addition detonation occurs, not only does the power drop, but there is also a risk of valve burnout). So, in general, we can conclude that the main symptoms are exactly the same as with incorrect setting of the ignition timing.

What do 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).

Causes of knock sensor malfunction

As for the reasons why problems arise with the knock sensor, these include the following breakdowns:

• Loss of mechanical contact between the sensor housing and the engine block . As practice shows, this is the most common reason. Typically, the sensor itself has a round shape with a mounting hole in the middle, through which it is attached to its seat using a bolt or pin. Accordingly, if the tightening torque in a threaded connection decreases (the pressing of the motor to the engine is weakened), then subsequently the sensor does not receive sound mechanical vibrations from the cylinder block. In order to eliminate such a breakdown, it is enough to tighten the mentioned threaded connection, or replace the mounting bolt with a mounting pin, since it is more reliable and provides a tight mechanical connection.
• Sensor wiring problems . In this case, there may be various problems, for example, a short circuit of the supply or signal wire to ground, mechanical damage to the wire (especially in places where it is bent), damage to the internal or external insulation, breakage of the entire wire or its individual wires (supply, signal), violation of the shielding braid. In this case, the problem is solved by restoring or replacing its wiring.
• Poor contact at the connection point . This situation sometimes happens if, for example, the plastic latch at the point where the sensor contacts are connected is broken. Sometimes, as a result of shaking, the contact is simply broken, and accordingly, the signal from the sensor or the power to it simply does not reach the recipient. To repair, you can try replacing the chip, correcting the contact, or using another mechanical method to try connecting two pads to the contacts.
• Complete sensor failure . The knock sensor itself is a fairly simple device, so there is nothing special to break there, and accordingly, it rarely fails, but it does happen. The sensor cannot be repaired, so in case of complete breakdown it is necessary to replace it with a new one.
• Problems with the electronic control unit . In the ECU, like any other electronic device, software failures can occur, which leads to incorrect perception of information from the DD, and accordingly, the unit makes incorrect decisions.

It is interesting that when a car owner contacts a car service center with complaints about the operation of the knock sensor, some unscrupulous repairmen immediately offer to replace it with a new one. Accordingly, take more money from the client. Instead, you can try tightening the torque on the sensor threaded mount and/or replacing the bolt with a stud. In many cases this helps.

Most common faults

In fact, cases of failure of the detonation detection device itself are not so common. In most cases, the reasons for incorrect operation are auxiliary factors, such as:

1. Damage to the wires connecting the control unit to the sensor. As a result, the unit does not read signals from the device; contamination of the metal part of the part;
2. corrosion (as a result of environmental influences);
3. chafing breaks and wires;
4. oxidation of one or both contacts.

Less commonly, there is a complete failure of the internal piezo element (plate) of the device. In most cases, the sensor cannot be repaired, and the repair itself is not entirely rational in terms of effort, time and money. The surest way is to buy a new product; fortunately, it is not expensive.

What are the effects of knock sensor malfunctions?

Is it possible to drive with a faulty knock sensor? This question interests motorists who are encountering this problem for the first time. In general terms, the answer to this question can be formulated as follows: in the short term, you can use the car, but at the earliest possible opportunity, it is necessary to carry out appropriate diagnostics and fix the problem.

Indeed, according to the principle of operation of the ECU, when a malfunction of the fuel knock sensor occurs, a late ignition is automatically set to prevent damage to the piston group parts if real detonation occurs during combustion of the fuel mixture. As a result, fuel consumption rises and dynamics drop significantly, which will become especially noticeable as the speed increases.

What happens if you turn off the knock sensor completely?

Some car owners even try to disable the knock sensor because under normal operating conditions and refueling with good fuel it may seem unnecessary. However, it is not! Because detonation occurs not only due to poor fuel and problems with spark plugs, compression and misfires. Therefore, if you disable the knock sensor, the consequences may be as follows:

• rapid failure (breakdown) of the cylinder head gasket with all the ensuing consequences;
• accelerated wear of elements of the cylinder-piston group;
• cylinder head crack;
• burnout (full or partial) of one or more pistons;
• failure of the jumpers between the rings;
• connecting rod bend;
• burning of valve plates.

This is due to the fact that if this phenomenon occurs, the electronic control unit will not take measures to eliminate it. Therefore, in no case should you turn it off and install a jumper from the resistance, because this is fraught with expensive repairs.

How to determine if a knock sensor is faulty

When the first signs of DD failure appear, a logical question is of interest - how to check and determine the malfunction of the knock sensor. First of all, it must be said that checking the knock sensor is possible without removing it from the cylinder block, or after removing it from its seat. Moreover, first it is better to do several tests when the sensor is screwed to the block. Briefly the procedure looks like this:

• set the idle speed to approximately 2000 rpm;
• With some metal object (small hammer, wrench), apply one or two gentle blows (!!!) to the cylinder block body in the immediate vicinity of the sensor (you can lightly hit the sensor directly);
• if the engine speed drops after this (this will be audible), it means the sensor is working;
• The speed remains at the same level - an additional check needs to be performed.

To check the knock sensor, a car enthusiast will need an electronic multimeter capable of measuring the value of electrical resistance, as well as DC voltage. The best way to check is with an oscilloscope. A diagram of the sensor operation taken with its help will clearly show whether it is operational or not.

But since only a tester is available to the average car enthusiast, it is enough to check the resistance readings given by the sensor when tapped. The range of resistance changes is within 400 ... 1000 Ohms. It is also imperative to carry out a basic check of the integrity of its wiring - whether there is a break, damage to the insulation or short circuit. You also cannot do this without the help of a multimeter.

If the check shows that the fuel knock sensor is working properly, but the error indicates that the sensor signal is outside the permissible range, then perhaps it is worth looking for the cause not in the sensor itself, but in the operation of the engine or gearbox. Why? Sounds and vibration are to blame for everything, which the engine can perceive as fuel detonation and incorrectly adjust the ignition angle!

Signs of a faulty knock sensor VAZ 2114

Signs of a malfunction of the VAZ 2110 knock sensor. Something always breaks in a VAZ. If the car owner knows the signs of a malfunction of the VAZ 2110 knock sensor (and, of course, other controllers) and knows how to read the errors shown by the ECU, this can make his life much easier. Not a single sensor is built into the car just like that; each one is designed by the designers to maintain and check the normal operation of various components.

From this point of view, the device that displays the level of detonation is particularly noteworthy. As long as the engine is running normally and no explosions occur, the engine can be said to be asleep. The car control system uses tabular, optimal parameters, giving instructions to the motor. However, if detonation occurs, the sensor instantly measures its strength, transmits the data to the on-board computer, and it reduces the advance angle. The correction occurs until the joint efforts of the motor control unit and the ECU stop the detonation, after which the sensor again seems to hide and fall asleep.

Thanks to such actions, all the troubles and dangers that arise from a detonating fuel-air mixture are prevented. And there are not so few of them, and they can sometimes cause significant damage to the engine unit in particular and the car as a whole. Signs of a malfunction of the VAZ 2110 knock sensor will help its owner understand what is happening with his car and take appropriate measures in a timely manner. About what visual points you should pay attention to, first of all, in order to detect a DD malfunction in time, and how to prevent it.

What you can notice first The knock sensor itself is quite reliable and does not fail very often. However, its performance should be checked in case of uncharacteristic behavior of the engine: a clear drop in engine power; “dullness” of the engine, increased speed at low speeds; deterioration of car acceleration; increased fuel consumption. It can reach +10%; smokier than usual exhaust. Tapping fingers and sudden jerks in movement may also be observed, but these are more individual reactions. Additional check Regarding electronic warnings.

Unfortunately, the control system often makes mistakes. So before trusting her information, it is worth conducting additional verification. Code 34 indicates failure of the DD. However, to make sure of this, you need to reset the self-diagnosis results, make a circle a couple of kilometers around the house and look at the readings again. If there is no error signal, it means that either the on-board computer was mistaken, or the sensor operates intermittently due to loose or oxidized contacts. Code 325 reports a broken DD. But often the unit records malfunctions of the throttle position sensor in its memory under these numbers. To check the assumption, you need to go into the menu and look at the voltage data on the suspected sensor: if the TPS is acting up, it will jump, while the detonation readings remain normal.

Searching for the cause As already mentioned, the DD is a surprisingly robust device. In most cases, it is enough to look for an open circuit, and first check the terminals. The wires ring if the self-diagnosis does not light up immediately, but when the engine spins above 3000 rpm. If the electrics are in order, the knock sensor itself is checked. It is located on the left in the direction of travel, where the air filter is located.

It is difficult to get to it, since the sensor is located between the cylinders - this allows it to take readings from the entire block. The sensor is dismantled. To do this, you will need a 13 socket key if your machine has a single-pin DD, and a 22 socket if it has a two-pin one.

Take a voltmeter with good sensitivity and set it to a mode of up to 200 MV. If there are 2 contacts, the sensor connectors are connected to the device. On another type of sensor, one probe is thrown onto the contact, the second – onto the body. Using a screwdriver, bolt or heavy pen, tap the body with varying strength (but without zeal). The voltmeter readings should fluctuate: the more noticeable the shock, the larger the jump.

If the device does not respond to influences, you need to change the sensor. Sometimes people try to save money on it by buying a used one, but this is not worth doing: a new one costs 200-300 rubles, which can be considered quite affordable, and a used one may be in even worse condition than a removed one. If all checks have been carried out and even the DD has been replaced, but signs of a malfunction of the VAZ 2110 knock sensor remain, then the problem is not at all with it.

Detonation is caused by other factors, among which the first place is gasoline poured in an untested place. However, other factors may also have an effect: compression problems, flooded or burnt-out spark plugs, etc. If you are confident in the integrity of the knock sensor, you will have to dig much deeper into the insides of the car.

Where is the knock sensor on a VAZ 2114

I’ll start today’s article with a story about what a knock sensor (DS) is and why a car engine needs it. This sensor is necessary, as the name implies, in order to monitor detonation in the engine, as well as knocking noises that indicate malfunctions.

Each knock causes the sensor to produce a pulse with a certain voltage. After this, the pulse goes to the controller, which performs subsequent processing. The controller adjusts the ignition timing depending on the size of the received impulse; the whole process takes a few fractions of seconds, so most often we simply cannot feel anything.

DD belongs to that category of automotive sensors that fail very rarely, for which a HUGE driver’s THANK YOU to him and his creators!

Where is the knock sensor located?

The VAZ 2114-2115 knock sensor is located between the second and third cylinders on the engine block; it can be one- or two-contact.

OPERATIONAL CHECK

If typical signs of a malfunction are detected, it is necessary to check the operation of the DD. To do this you will need a regular screwdriver and a tester.

A tester, also known as a multimeter, can be purchased at any automotive store. It is inexpensive, about 500-600 rubles, and will come in handy in the garage many times (it is used to check all systems and devices of the car that consume electricity), so there is no need to skimp on the device.

The DD functionality check is performed as follows:

1. We dismantle the sensor (how to do this is written in the next section of the article);
2. We connect the multimeter probes to the DD contacts (if it is two-contact), if it is single-contact, the first probe to the wire, the second to the device body;
3. We switch the tester to voltmeter mode and set the upper measurement limit to 200 mV;
4. Tap a screwdriver (or any metal object) on the sensor body;
5. If the device is working properly, the multimeter will show voltage surges, the magnitude of which should be directly proportional to the force of the impact (this indicates that the device retains the ability to convert mechanical energy into alternating current). If the multimeter readings do not change, the DD does not work.

If you find out that the device itself is working properly, but DD errors are displayed on the on-board computer or the car is not working as it should, the problem is most likely in the oxidized contacts of the sensor. Treat them with WD-40 or a similar solvent, install the DD in place and check the result. If that doesn't help, replace the knock sensor.

To your attention errors in the knock sensor VAZ 2114

• Error code 0325 - there is a break in the wiring that supplies power to the DD. Most often, the cause of this error is oxidized contacts of the knock sensor; a wiring break occurs extremely rarely. It is necessary to clean the contacts, this will give a positive result, at least it will not get worse. In addition, this error can be caused by the timing belt, so if after cleaning the DD contacts the problem remains, check the timing belt, most likely it has jumped a couple of teeth. Align the belt to the marks and check again if the error appears.
• Error code 0328 - as a rule, indicates faulty high-voltage wires. However, the possibility of the timing belt jumping cannot be ruled out.
• Error code 0326 , as well as 0327 , mean an excessively weak (low) signal from the knock sensor. To eliminate errors, it is necessary to clean the VAZ 2114 DD connection contacts. The tightening torque of the sensor is also important; if the tightening is weak, the above errors may appear.

Diagnostics and replacement of the knock sensor

Symptoms of a problem

If you begin to notice that your car’s engine is running unevenly (troiting), or its dynamics have deteriorated and the “CHECK ENGINE” indicator lights up on the instrument panel when you start to climb or when accelerating, then you should check the knock sensor for possible malfunction. The following instructions will help you diagnose and replace the knock sensor yourself.

Examination

So, on VAZ 2110, 2112, 214, 2115, replacing the knock sensor begins with reading engine fault codes:

• Error code 0325 indicates that there is a break in the electrical circuit of the sensor circuit.

It is necessary to carefully inspect and, if necessary, “ring” the entire circuit and clean the contacts in the sensor connectors, since the main cause of this error is oxidized contacts. In addition, it is necessary to check the timing belt, namely, whether it is installed correctly according to the marks; perhaps it has become loose and has jumped several teeth.

• Error number 0328 indicates a high signal level from the knock sensor.

In this case, you need to pay attention to high-voltage wires. This error is issued when there is a breakdown of the power supply and the piezoelectric element, as well as when the valve clearance is increased. Again, recheck the timing belt.

• Error codes 0326 and 0327 indicate that the signal level from the sensor is too low.

As in previous cases, we check the electrical circuit circuit; with the sensor removed, we treat the sensor and its contacts with special anti-corrosion agents. Pay special attention to the tightening torque of the sensor, which should be 10-24 N*m. If the instrument panel does not signal you with the “CHECK ENGINE” indicator light, then replacing the knock sensor on VAZ 2114, 2110, 2115 is accompanied by checking it with a voltmeter, for which:

• In the multimeter, set the voltmeter mode and enter the reading limit of 200 MV;
• On a two-contact sensor (broadband type) we connect the multimeter probes to the contacts, and on a one-contact (resonance type) - one to the contact, the second to the sensor body;
• Lightly tap the sensor body with a subsequent increase in impact force with a metal object (screwdriver or bolt) and observe the voltmeter readings;
• When impacted, a voltage surge should be observed: a stronger impact means a higher surge, otherwise the sensor definitely needs to be replaced.

Also, replacing the VAZ 2115 knock sensor may be accompanied by checking it with an ohmmeter, in which the resistance reading should be on a scale of 1-10 MOhm.

Checking with a multimeter

Replacement

Replacing the knock sensor of a VAZ 2112, 2110, 2114, 2115 is not difficult at all, so this instruction will not contain any additional video materials. As mentioned above, sensors of both types are installed on the engine cylinder block. The entire replacement process is as follows:

• With the ignition off, disconnect the wire connector from the sensor, or one wire for a resonant type of sensor;
• In the first case, use a key set to “13” to unscrew the bolt securing the engine...

Replacing the knock sensor VAZ 2115

VAZ 2110 knock sensor replacement

...and in the second, using a key set to “22”, we unscrew the block from the body and dismantle the device itself;

• Install in reverse order.

Advice! When installing, pay special attention to the cleanliness of the sensor seat and its tightening torque (10-25 N*m)

How to check the knock sensor of a VAZ 2114-2115

• Prepare the end face at “13” or “22” (depending on the type of sensor).
• Multimeter or voltmeter.
• Screwdriver.

Sequencing:

1. Remove the sensor from the engine block.
2. Turn on the voltmeter or multimeter in operating mode with a limit of 200 mV.
3. Connect the multimeter electrodes to the knock sensor terminals, then use a screwdriver to tap the part body.
4. While tapping, observe the changes on the device display; depending on the strength of the blows and frequency, the voltmeter readings should change. If your knock sensor readings do not change, it is faulty and needs to be replaced.

VAZ knock sensors come in two types:

1. Resonant (made in the shape of a barrel).
2. Broadband (made in tablet form).

These sensors are completely different, so before you buy a knock sensor for a VAZ 2114 or 2115, check which one you have installed.

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 fundamental difference between a resonant type device is that it is capable of capturing only noise at the detonation frequency.

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.

Why do you need a knock sensor on a VAZ 2114?

The operation of the VAZ 2114 power unit may be accompanied by the appearance of detonation. It has a bad effect on the engine, creating parasitic vibration and having a destructive effect on the main elements of the internal combustion engine.

Damage and metal fatigue gradually accumulate in the engine, which results in the imminent need for major engine repairs. A combination of electronic control units and DD is working to eliminate detonation. The meter detects the occurrence of non-optimal ignition of the fuel-air mixture, and the main module corrects the spark advance angle.

Causes of detonation

We have figured out the features of this effect, so now we need to figure out why this very detonation can occur.

When detonation occurs continuously, the engine and its components overheat. If this effect is not prevented, the power unit will soon fail completely. It is not a fact that even a major overhaul will allow it to be restored.

Examination

Purpose of the knock sensor

Early VAZ 2114 models used a resonant knock sensor. Subsequently it was replaced by broadband. Both DDs have a similar principle of operation, but differ significantly in design. Therefore, they are absolutely non-interchangeable.

The broadband DD is made in the shape of a round torus. It is attached to the engine with a bolt passing through a hole located in the center. There is a two-pin connector on the side of the torus for connection to the main module.

Fixing the resonant knock sensor does not require the use of a bolt. On one side of its body there is a thread with which it is screwed into a seat on the cylinder block.

A piezoelectric element is located inside both types of DD. It is sensitive to vibration and shock. The difference between the resonant DD is its narrower control range.

An electrical signal of a certain frequency and amplitude is generated inside the knock sensor. It goes to the ECU. The electronic control module monitors and analyzes the received signal. When detonation is detected, the ECU adjusts engine operation according to the established algorithm.

Eliminating detonation minimizes parasitic loads on the engine. As a result, the engine resource increases. This is what the knock sensor affects.

Useful tips

Recently, cases of selling defective spare parts and sensors without the necessary internal contents have become more frequent. Therefore, immediately after purchasing the product you need, it is recommended to check its performance with a multimeter. You should know that on older VAZ 2114 models the knock sensor (resonant) differs from modern products (broadband) in price, design features and operating principles. Therefore, you should buy a product that is designed specifically for your car model. A device with a resonant type of operation cannot be replaced by modern products without modifying the ECU.

Location of the knock sensor on the VAZ 2114

The location where the DD is located is selected in such a way that the sensor has the greatest sensitivity. Therefore, the DD is mounted directly on the cylinder block. You can find the location by tracing the wires coming from the electronic engine control unit. It is easier to do this on a VAZ 2114 with an 8-valve engine, since its engine compartment layout is less loaded. On a car with 16 valves, it is more difficult to determine what each loop and sensor is responsible for.

Tightening torques for brake system connections

Sensor cost

On VAZ 2114 cars of early production years there is a Lada sensor 21120385501001. It has an extremely low prevalence and because of this its price is high and amounts to 800-1300 rubles. The only commonly found analogue is General Motors 21120-3855010-01 with a cost of 1600-1800 rubles.

The original broadband DD has article number 21123855020. Its price is much lower and amounts to 100-160 rubles. Its good analogues are presented in the table.

Table - Good analogues of the original VAZ 2114 knock sensor

Step-by-step replacement procedure in case of malfunction

1. In order to change this sensor on a VAZ-2114, no special skills are required.
2. First of all, open the hood and look for DD with the engine off.
3. If you have a broadband sensor, then you need a 13 key, and if the sensor is single-contact, then a 22 key will be useful.
4. Then in the first case we unscrew the nut to 13 and in the second case the sensor is unscrewed with a head to 22.

As you can see for yourself, replacing the knock sensor on a VAZ-2114 is not difficult.

Source

Methods for checking a knock sensor

If signs of malfunction of the DD appear, then you should check for errors. About problems with the knock sensor they say:

• code 0326, indicating the signal level is too high;
• code 0327, indicating a low signal level, for example, due to the fact that the tightening torque does not correspond to the nominal one;
• code 0325, there is an open circuit in the circuit

You can check the DD by measuring the resistance.

You can check the DD with a multimeter. To do this, check the presence of voltage at the sensor outputs when tapping it with a metal rod.

Steering torques

Self-replacement of sensor 21120385501001 on a VAZ 2114

Replacing the resonant DD is carried out according to the instructions below.

• .De-energize the on-board network.

• Remove contact with DD.

• Unscrew the sensor.

• Dismantle the DD.

• Install the new one in reverse order.

Replacing broadband DD on VAZ 2114

The broadband DD is replaced according to the algorithm below.

• Disconnect the terminal and unscrew the sensor.

• Remove DD.

• Install the new wideband sensor in reverse order.