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The main signs of a malfunction of the DMRV (VAZ). The main symptoms of a malfunction of the DMRV (VAZ) Characteristic symptoms of a malfunction

Good day, dear readers of this blog! Today we will talk about how to check the mass air flow sensor on a VAZ 2114. The testing method is so simple and effective that I was surprised when I learned it! I advised it to friends, they said, “Where have you been before?”

I won’t bore you, let’s get straight to the point

Looking ahead, dear car enthusiasts, I want to warn you a little. If you contacted the service, and you there right away without any measurements and checks diagnosed a breakdown of the mass air flow sensor, then 90% is a scam. Checking the sensor, although simple, is not possible without some equipment.

Anyone who has previously dealt with a problem with a sensor will probably immediately remember the symptoms of a breakdown. But since this article is not only for “experienced” ones, but for all car enthusiasts, then of course I will list them.
It is clear that a malfunction of the mass air flow sensor has a negative effect on the operation of the engine as a whole, in particular on the 1.6. The Check light comes on and the car starts to stall. And the thought of checking this sensor does not immediately come to mind. As a result, fuel consumption increases, and the car is also difficult to start when hot.

About verification

The most accurate method for checking a malfunction is to replace it with one that is known to work, but not everyone has this opportunity and this is normal. Therefore, I suggest, as an option, to travel without a sensor. So, we open the hood, direct our gaze to the area of ​​the air filter, and see a plastic “bummer” with a chip on the air intake pipe. We remove this chip from the sensor. The ECM will go into emergency engine operation mode, in which the fuel mixture is prepared only according to the throttle position. Now start the engine and look at the tachometer. The speed should be about 1500 rpm. We get underway and, after driving a little in various modes, we notice how the car behaves. If you feel that traction has appeared and the car is “fluttering,” we can state that the mass air flow sensor is dying.

As for more accurate diagnostics, here we need a multimeter.

I think many people have it. If not, ask your acquaintances and friends; people call him a “tester.”

The bottom line is that we need to measure the voltage at the sensor terminals in the connected state, that is, the chip must be plugged into the sensor.

To avoid damaging the insulation, you can do this. We take two thin needles and tightly wrap them to the multimeter probes. The main thing is that the contact is good. If you have a cambric, it is better to use it to fix the needles on the probes.

Now we look in the sensor chip yellow and green wire. Yellow – plus, Green – mass. Carefully insert the needles under the insulation of the wires and hold or fix it all.

Now switch the multimeter to DC measurement mode and set the measurement limit to a lower value. If there is a limit of 2 Volts, then it will be enough.

Now turn the key, turn on the ignition, but don’t start! We look at the multimeter display and compare our result with the following values:

Drawing conclusions

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But to implement them, it is necessary that the sensors informing the controller do not deceive it - only under this condition do the processes in the cylinders proceed normally, the engine develops sufficient power without consuming excess fuel and without causing much harm to the environment. One of these sensors measures the amount of air entering the cylinders and generates a corresponding signal to the controller. This can be an absolute pressure sensor (MAP sensor) or a mass air flow sensor (MAF). We see the latter on many cars, including VAZ ones.

Malfunctions of the mass air flow sensor, naturally, lead to one or another malfunction in the engine - jerks, failures, difficult starting, etc. - an incorrect assessment of the amount of air consumed in the cylinders turns out to be approximately the same as clogging the jets of a textbook carburetor. But “calculating” problems in the mass air flow sensor, even with serious diagnostic equipment, is sometimes difficult. In such cases, many do the traditional thing: they replace the suspected device with a known good one - but only on the condition that the new one is of the same model. The fact is that on VAZ cars, depending on the year of manufacture and the type of controller, you can find different mass air flow sensors.

The first was the frequency mass air flow sensor of the GM control system. It was also used in the domestic analogue “January” of the 4th series (photo 1). Cars of this configuration did not last long on the assembly line - the frequency sensor was replaced by an analog model HFM-5 from Bosch - its number is 0280218004 (photo 2). It is not interchangeable with GM - the connectors and mounting points are different. The German sensor is dismountable, consisting of two parts - a housing and a measuring element. The latter is secured in the case with two screws with “secret” heads. True, nowadays you can buy the necessary tools in auto parts stores. The measuring element is a compact thing, but it is expensive - in Moscow from 1300 rubles. and higher. Having removed this part from a new car, in exchange, of course, they will put a dummy, and everything that follows is the “personal grief” of the car buyer. The market is full of such “mass air flow sensors without a housing”... It is unwise to buy a measuring element without a housing: it is very possible that it is faulty or the wrong model. Bosch only sells assembled sensors in traditional yellow cardboard packaging. Let us remind you that the store may not accept a return air flow sensor purchased from the “wrong system” if the motorist does not provide a certificate from the service, and it is often difficult to obtain one. An unnecessary expensive unit will remain as a keepsake.

The third version of the mass air flow sensor is 037. (Here we are talking about the last three digits in the designation.) This is a further development of the 004th sensor from Bosch. Such a sensor is used today on most VAZ cars traveling on the roads, including Niva and Chevrolet Niva. Externally, 004 and 037 are almost indistinguishable - just look at the number (photo 3). Recently, additional markings have appeared on products: now there are numbers on both the body and the measuring element - they must match. The main difference is inside the mass air flow sensor. In photo 4 on the right is the 037th sensor. It has a different design of the measuring element, with a characteristic cutout (when purchasing, it makes sense to remove the plug and look inside).

But now a new control system has appeared - Bosch-M7.9.7, which has its own, 116th, mass air flow sensor. It is not interchangeable with the previous ones, although its body is the same. To avoid confusion, a green circle was initially applied to the body (photo 5). There are numbers on both the body and the measuring element (photo 6). The latter determines the purpose of this mass air flow sensor - the design has been changed again (photo 7). To prevent elements from being replaced on the way from the factory to the consumer, the kind German designers installed other secret screws. Eh, naive! The required tool is already sold on the Russian market. Carefully inspect the mass air flow sensor: when unscrewing the secret screws, their coating is usually damaged. If you notice, draw your own conclusions!

Car enthusiasts are well aware that an injection engine is a rather complex structure. But it is this that provides the car with a lot of advantages. After all, such an engine can operate in different modes, if we talk about the load. Normal operation can only be ensured if the car's control - the electronic brains - works correctly. Their task is to accurately determine the ratio of gasoline and air in the fuel that is supplied to the engine.

Mass air flow sensor VAZ 2114

A part such as the DMRV VAZ 2114 is designed to determine how much air enters the engine. The acquired indicators are very important, because it is depending on them that the required amount of gasoline that needs to be supplied to the engine is determined.

The part has a special sensitive component, which is a thin thread made of platinum. During the working process, it heats up to high temperatures. Temperatures can rise to thousands of degrees. Afterwards the thread is cooled under the influence of passing air.

The temperature to which a given thread can cool is an indicator of the amount of air passing through. It is believed that the lower the temperature, the higher the conductivity of platinum. Accordingly, the thread will be able to conduct more current that flows to it.

Purpose and principle of operation

Many car owners are concerned about how much it costs to purchase such a sensor. It turns out that the DMRV 2114 has a considerable cost, it varies between 2-3 thousand. In this case, you can use both imported products and domestically produced parts. You shouldn’t be surprised that there are corresponding reviews about domestic models.

But you shouldn’t always trust reviews; it’s better to try the products in practice. Although you can find a lot of negative reviews about domestic sensors, they are more accessible.

This sensor allows the engine to operate in different operating modes, involving different loads. If we consider the operation of the device, it consists in creating a working mixture of air and gasoline. More precisely, the mixture includes gasoline vapors. The direct task of the product is to measure two indicators that are interconnected:

  1. Reaction time.
  2. The amount of air that is consumed for the reaction.

If the measurements are accurate, the device can determine what mixture the engine requires. This allows the system to obtain information about the required proportions. There are also situations when the sensor does not work correctly, producing incorrect values.

In this case, the mixture created in the system will not correspond to the current operating mode. As a result, power may decrease and consumption will likely increase. Possible consequences may include a deterioration in the dynamics of the car and a disruption in the response of the car.

Attention! The response of parts from different manufacturers may vary significantly. It is important to take this point into account when checking the operation of the sensor.

What does it indicate a malfunction?

If the DMRV sensor of the VAZ 2114 has stopped working, then this can be noticed by the behavior of the car if you are extremely careful. A non-working part can make itself known through a number of symptoms when it comes to the operation of the injector. At the same time, you need to understand that the malfunction will not be noticed suddenly, it appears gradually.

At first, fuel consumption increases and floating speeds are observed. Then everything happens progressively, the operation of the engine becomes unstable. Many car enthusiasts face similar problems, especially for owners of front-wheel drive cars. Initially, the car icon lights up, the speed begins to fluctuate, and then the fuel consumption increases more and more.

The fact that the air flow sensor on the VAZ 2114 is faulty can be calculated by certain signs:

  • The engine power has dropped significantly, you can feel it when driving;
  • the car requires more fuel;
  • the engine does not start well when hot;
  • the car gives a Check Engine signal;
  • the car picks up speed poorly and accelerates slowly;
  • stalls if you try to change gear;
  • If it is idling, then failures are noted.

If the air consumption of the VAZ 2114 does not adhere to the norm, and the sensor cannot be repaired, then the corresponding signal may not light up. In this case, the malfunction can be determined using the on-board computer. It is also worth checking the signal level of the sensor.

The results of testing with a multimeter, indicating the performance of the mass air flow sensor, are shown in the table.

A low level indicates the following conditions:

  • the sensor does not work;
  • no connection - the problem may lie in the contacts;
  • there is an open circuit in the connection circuit;
  • the mass has broken or oxidized, this often happens;
  • short circuit of signal wires, their incorrect connection.

If you encounter any accompanying symptoms, do not immediately go to the store for a new one. First of all, you need to make sure that the old part can no longer be repaired. It is also worth clarifying that the problem lies precisely in the detail. If it is not possible to repair the part yourself, you can always contact the service.

Removal and replacement

If the VAZ 2114 air sensor was checked, and the check confirmed incorrect operation, then you should think about replacing it. Experts do not advise rushing to throw away a part, even if it is not working correctly. Sometimes it happens that after cleaning the contacts it starts working again. It is worth paying attention to this possibility if you would not like to replace the part.

When it is not possible to revive an existing part, you should go shopping. A new part will not be cheap, it is an expensive pleasure. That is why experienced technicians advise initially checking the functionality of the old sensor before spending your savings. To replace the product, you will need to prepare a flat-head screwdriver, as well as a 10mm wrench.

The sequence of actions should be as follows:

  1. Initially, the ignition is turned off, the hood is opened, and the negative terminal is removed from the battery.
  2. Now you have to determine where exactly the sensor is located. Usually there are no difficulties with its location. In the engine compartment you can see the air filter unit; it is made of plastic. This sensor is located on its rear part; it is usually mounted on the air filter pipe.
  3. Next, the clamp made of metal is removed and the product is connected to a corrugated hose through which air is supplied.
  4. You will need to pull off the corrugated hose.
  5. Next, the contact block is removed, and it should be taken into account that there is a button on the bottom of the plug. When pressed, the spring wedge is released. This is necessary to freely pull out the block.
  6. A pre-prepared 10mm wrench is needed to unscrew the bolts one by one; they are used for fixing. By the way, the second of them is located on the lower part of the case.
  7. All that remains is to remove the sensor.

Useful video

You can find additional useful information in the video below:


The VAZ-2114 engine can have 8 valves or 16. The latter option is more powerful. In order for the car not to waste a lot of fuel and to work properly, it is necessary for the mass air flow sensor to produce the correct indicators. Its primary task is to measure the amount of air consumed and the reaction time. The accuracy of the indicators allows the controller to determine in what proportion the air and fuel need to be mixed. If the device shows inaccurate data, then the resulting fuel mixture does not correspond to the engine operating mode. In this case, fuel is consumed in large quantities and power is reduced.

What should be the air flow for the VAZ-2114

During normal operation of the sensor, the engine of this machine consumes from 10±0.5 kg of air per hour of operation. If the quantity decreases, then the dynamics of the car decreases, which saves fuel, and if it increases, fuel, on the contrary, is greatly consumed. In cold weather, this can lead to problems with starting the engine. If the sensor readings deviate from the real ones, then the engine begins to work intermittently, or even does not start at all. What can cause sensor readings to deviate? Let's try to find out.

Causes of sensor failure: when replacement is required

The error of the sensor significantly worsens the functioning of the car as a whole, but this mainly affects the operation of the controller. When using a sensitive controller, this can lead to floating idle speed, but there will be no noticeable dips during acceleration. In general, the readings should be normal, so you need to monitor this and, in case of malfunction, replace the device.


The crankcase ventilation system can cause inaccurate readings. If the throttle is closed, then the gases are diverted through the line into free space. A certain amount of these gases goes into the idle line, where it comes into contact with the mass air flow sensor. Next, the resin settles on the resistor, which leads to errors in the sensor readings.

You can recognize a poorly functioning sensor by the following signs:

  • failures in work;
  • when changing gears, the internal combustion engine acts up;
  • the car is not capable of accelerating much;
  • fuel is consumed in large quantities;
  • engine power is reduced;
  • The Check Engine signal appears.

If these signs are absent, then the malfunction can be determined by the error that appears on the on-board computer.

In addition, you can diagnose the sensor signal level.

The mass air flow sensor is necessary for efficient engine operation in different modes. The function of this device is to create a working mixture of air and gasoline vapor. The task of the VAZ 2114 air flow sensor is to measure two interrelated indicators:

  1. Amount of air consumed;
  2. Reaction time.

The accuracy of measuring the air consumption of the engine allows the controller to determine in what proportion it is necessary to mix air with fuel. If the sensor produces incorrect values, the resulting air-fuel mixture does not correspond to the current engine operating mode. This leads to a decrease in power, an increase in fuel consumption, and a deterioration in the dynamics and response of the car.
The response of controllers from different manufacturers to these parameters may differ.

For example, January-5.1, in case of slight overestimation or underestimation of values, determines the error of the mass air flow sensor based on the readings of the oxygen sensor, thus adjusting the duration of fuel injection. Increasing the sensor response time will cause the controller to not keep up, and at the time of acceleration you will notice “dips” of the engine. The same sensor error when using a more sensitive Bosch controller will lead to floating idle speed, although there will be no noticeable dips during acceleration.

A 1.5 liter VAZ 2114 engine with a working mass air flow sensor at 850-950 rpm consumes from 10±0.5 kg of air per hour of operation, and at 2000 rpm - from 19 kg to 21 kg. If the amount of air consumed at the same speed decreases, the dynamics of the car also decreases, but fuel is saved. Conversely, increased air consumption leads to increased dynamics and higher fuel consumption. In this case, it may be difficult to start the engine in cold weather. If the sensor readings deviate from the real ones by 2-4 kg, the engine will begin to become very capricious and “dull”. Disabling the sensor will force the motor to continue operating in emergency mode.

Causes of malfunction

Common to most domestic cars, the reason why the VAZ 2114 air flow sensor breaks is hidden in the crankcase ventilation system. It has two circuits that ensure operation with the throttle valve open or closed. If the throttle is buried, crankcase gases are discharged along the line (d=1.5 mm) into the space available behind it. A certain percentage of these gases accumulates in the idle line, where it comes into contact with the film-coated MAF resistor. It is also sensitive to fluctuations in the gas mixture in the intake system. The resin settles on the surface of the resistor, and the sensor begins to “lie.” Because of this, the idle air control sticks, and it begins to jam when starting the engine.

Symptoms of a problem

A non-working VAZ 2114 mass air flow sensor leads to the appearance of a number of symptoms in the behavior of the injection engine. The malfunction appears gradually, starting with an increase in fuel consumption and floating speed, ultimately destabilizing engine operation.

From personal experience using a front-wheel drive car as an example, I can say that I encountered the following problem: first the injector icon came on, then the speed began to fluctuate greatly and fuel consumption almost doubled.

You can calculate a non-working VAZ 2114 air sensor using the following criteria:

  • failures when idling and under load;
  • The internal combustion engine stalls when trying to change gear;
  • decreased dynamics, the car accelerates slowly;
  • fuel consumption increased;
  • engine power has dropped;
  • hard to start when hot;
  • The Check Engine signal appears.

If the mass air flow sensor is already dead, the Check Engine light may not come on. Then the malfunction can be determined by the error generated by the on-board computer. Diagnostics of the MAF signal level will also help. A low level may indicate the following:

  • There is no MAF connection;
  • malfunction in the sensor connection circuit (break);
  • the ground in the connection circuit is broken or oxidized;
  • the signal wires are broken or incorrectly connected, perhaps they are short-circuited;
  • engine control unit malfunction;
  • DMRV does not work.

If you notice the above signs, do not rush to buy a new sensor. It is by no means the cheapest and will cost 1500-4000 rubles. First of all, make sure that this is the reason. You can check and clean the old one at a service center or yourself if you have the necessary equipment.

Checking the mass air flow sensor

Before you start experimenting, take the time to read the service manual. It describes in detail what a mass air flow sensor on a VAZ 2114 is and how to replace it.

We are looking for a sensor. Open the hood and find the air filter pipe. The mass air flow sensor is located on it, which determines the flow of air passing through the filter. I will give several options on how to check the mass air flow sensor yourself.

  • Disable the sensor. Disconnect the block with wires from the connector by pressing the latch located below. Start the engine (1500 rpm or more). The controller understands the shutdown of the mass air flow sensor as an emergency condition and prepares the fuel-air mixture based on the position of the throttle valve. Try driving a short distance. If the car accelerates noticeably faster, this indicates a non-working mass air flow sensor. I would like to note that in the disabled state for ECUs Y7.2 and M7.9.7. RPM doesn't increase!
  • Replacing the controller firmware. The original ECU firmware could have been replaced with an alternative one. In such a situation, we do not know which algorithm is prescribed in the case of operation in the mode discussed in the first paragraph. The throttle valve has a stop under which you need to place a thin plate (about 1 mm) to raise the speed. Then you need to disconnect the chip with the sensor. If the sensor is faulty, the engine should stall. If the engine is running, then the reason is due to the firmware features: the IAC steps are written incorrectly.
  • Voltage measurement. Testing gives good results when working with Bosch sensors. You will need a multimeter. Select the DC voltage measurement mode and set the maximum value to 2 V.

The connection diagram for the VAZ 2114 looks like this:

  1. yellow – incoming signal;
  2. gray with white – power output;
  3. green – grounding;
  4. pink with black – output to the main relay.

The colors may be different, but the sequence of connectors is the same.

Next, you need to turn on the ignition with the engine off. Connect the red (positive) probe of the tester to the yellow output, and the black (negative) probe to the green. Multimeter probes are inserted along the specified wires directly through the rubber seals of the connectors without damaging the insulation. For prevention, I recommend moistening the probes with WD-40. Intermediates or needles are not recommended due to the additional error they introduce. Measure the voltage. Compare the result with the table:

A newly installed sensor gives an output voltage of 0.996–1.01 V. Over time, it increases. A higher value means a higher percentage of wear.

Voltage data from the sensors is recorded by the on-board computer and can be viewed by selecting the appropriate group of parameters.

  • Inspection and cleaning. Use a Phillips screwdriver to loosen the clamp holding the air intake pipe. We remove the corrugation and check whether there are traces of oil and/or condensation inside it, as well as on the inner surface of the sensor. Normally they shouldn't be there. The sensing element of the mass air flow sensor often breaks due to dirt getting on it. This can easily be avoided by regularly replacing the air filter. Reasons for oil getting into the air flow sensor:
  1. the permissible oil level in the crankcase has been exceeded
  2. The oil separator of the ventilation system is clogged

The sensor is attached to the pipe with two screws. We unscrew them with an open-end wrench (x10) and remove the sensor itself. There is an entrance at the front, which must be protected from the leakage of untreated air with an o-ring rubber seal. If it is missing or remains in the filter housing, dust clogs the sensor input grid. It needs to be cleaned, the seal installed, the leaks checked and the sensor put back in.

  • Comparison with a working sensor. From personal experience, I was convinced that the most accurate test is to install a sensor that is known to work and compare the behavior of the engine with the “native” one.

In addition to the options considered for how to check the mass air flow sensor yourself, you can also contact a service center that has special equipment and carry out 100% diagnostics, for example, using the method of evaluating an oscillogram.