A modern car engine is a high-tech unit of complex design, and this unit is “stuffed” with various electronics. There are a large number of different sensors that monitor its operation and many associated elements, so when it comes to diagnostics and repairs, many simply do not know where to go and what exactly needs to be checked. However, in reality, not everything is as complicated as it might seem at first glance: almost all sensors are subject to inspection and replacement, no exception. The main thing in this matter is to know how and what needs to be done.

But before I tell you how to check the air flow sensor of a VAZ 2114, I would like to say a few words about it itself. Just so, it will be easier for you to understand the information presented below.

So, the main task of the mass air flow sensor is to control the balance of air and fuel, which form the fuel-air mixture. It is this sensor that monitors what kind of mixture is formed - rich or too lean - and “transmits” this information to the ECU, on the basis of which further appropriate adjustment is carried out.

If the mass air flow sensor fails, then this whole chain collapses: the engine begins to act up, traction is lost, which ultimately can lead to complete engine failure.

Signs of a malfunction of the VAZ 2114 mass air flow sensor?

• Floating idle speed.
• Engine won't start.
• Increased “appetite” of the motor.
• Poor engine dynamics.

Three ways to check the sensor.

Method one: disabling the mass air flow sensor.

1. You need to disconnect the sensor and try to start the engine.
2. The controller is operating in emergency mode.
3. The fuel-air mixture is prepared taking into account the position of the throttle valve, which the ECU informs about its position sensor.
4. We set the engine speed at 1500 rpm and try to drive a little; if the dynamics have improved and the acceleration has become a little faster, then the mass air flow sensor is faulty.

Method two: visual inspection.

The clamp attached to the air collector is removed from the corrugation. The surface of it and the mass air flow sensor is checked for traces of oil and condensate.

Method three (suitable only for modern mass air flow sensors) - how to check the mass air flow sensor of a VAZ 2114 with a multimeter?

The device sets a limit of 2 Volts.

The MAF pinout is as follows:

• a black and pink wire leads to the main relay;
• to the signal input – yellow;
• the green wire is grounding;
• white-gray wiring – voltage output.

Attention! Colors may vary depending on the sensor manufacturer.

Now turn on the ignition, but do not start the engine.

Connect the red probe of the multimeter to the yellow signal wire, the black probe to the green one.

The voltage at the output of the device can fluctuate between 0.966-1.01 V. Over time, this voltage can increase and the higher the value, the more faulty the mass air flow sensor. Now let’s take a closer look at the measurements themselves and what they mean:

• the sensor is working - the indicator is “0.1-1.02”;
• there is slight wear on the sensor – the indicator is “1.02-1.03”;
• the sensor will soon fail - the indicator is “1.03-1.05”;
• The sensor needs to be replaced - the indicator is “more than 1.05”.

Video.

When a malfunction of the mass air flow sensor occurs on VAZ 2114 vehicles with an injection engine, the symptoms can be very different. Everything can start gradually with a slight increase in fuel consumption and ending with unstable engine operation, floating speed, etc. From a personal example with a front-wheel drive car, I can say that I had a problem with this sensor. First, the injector icon began to light up, and then the speed began to fluctuate greatly. At the same time, fuel consumption almost doubled.

This situation continued for quite a long time, fortunately there was an on-board computer and the errors could be reset, thereby returning the engine condition to normal. But sooner or later the sensor had to be changed. To replace it you will need a minimum of tools, namely:

• crosshead screwdriver
• 10mm wrench or socket wrench

First you need to open the hood and disconnect the negative terminal from the battery, and then disconnect the block with wires from the sensor by pressing the latch from below:

After this, use a Phillips screwdriver to loosen the clamp that tightens the thick inlet pipe coming from the air filter. This is clearly shown in the photo below:

Now remove the pipe and move it slightly to the side:

Next, you can begin to unscrew the two bolts securing the mass air flow sensor to the air filter housing. It is most convenient to use a ratchet handle. One bolt is clearly visible in the photo, and the second is located on the bottom side, but access to it is quite normal, you can unscrew it without problems:

Then remove the air flow sensor and install a new one in the reverse order. You can buy a new mass air flow sensor for a VAZ 2114 at a price from 2000 to 3000 rubles, depending on what type of device you need. It is better to look at the part code of the old sensor before purchasing.

The mass air flow sensor, that is, the mass air flow sensor, serves to ensure the efficient operation of the power unit, regardless of its operating mode.

The role of the mass air flow sensor

The task is to create a mixture of gasoline vapor and air. The sensor is capable of measuring two indicators that are strongly related to each other:

• Reaction time;
• Amount of air used.

Receiving accurate data, the meter determines the optimal amount of components to create the proportions of air with fuel vapor. If the mass air flow sensor begins to produce incorrect values, the mixture will not correspond to the operating mode of the engine in which it is currently operating.

As a result, power drops, fuel consumption increases, response decreases, and acceleration takes much longer. Depending on the sensor, its delays may manifest itself in the form of dips during acceleration or floating speed at idle.

Optimal air flow

Since we are talking about the VAZ 2114, we should determine what air flow rate is optimal for its engine.

A working sensor under operating conditions of a 1.5 liter engine at approximately 900 rpm, the amount of air consumed will be from 10 kg with an error of 0.5 kg per hour. If you raise the speed to 2000, then the consumption will increase to approximately 19-21 kg.

When the amount of air decreases at the same speed, the dynamics will immediately begin to decrease, but at the same time fuel consumption will decrease. If the air flow increases, the dynamics will increase, and fuel consumption will also increase.

The sensor should not be allowed to deviate by more than 2-4 kilograms, since under such circumstances the operation of the engine will be very capricious and unpredictable.

Causes of failure

In fact, air flow sensors can only fail for reasons that are hidden in the crankcase ventilation.

This ventilation system is dual-circuit; it is responsible for operating in two modes - with the throttle valve closed or open. If the damper is closed, gases from the crankcase exit through the line. But a certain proportion of gases accumulates inside the idle line. In this case, the gas comes into contact with the resistor of our sensor, although it is covered with a film. Due to the resin that settles on the resistor, the mass air flow sensor begins to produce incorrect information. From here a chain of malfunctions arises.

Signs of breakdown

If the sensor fails, a variety of symptoms may appear, but ultimately this will lead to a malfunction of the motor. At first, the engine’s appetite for gasoline may increase, then floating speeds will be observed, etc.

There are several characteristic signs that indicate a breakdown of the mass air flow sensor:

1. Dips are observed when the engine is running under load and at idle;
2. The car begins to accelerate more slowly, the dynamics noticeably suffer;
3. When changing gears, the engine turns off;
4. Power drops;
5. Fuel consumption increases;
6. When the engine is hot, the engine is difficult to start;
7. The Check Engine light comes on on the dashboard.

If the sensor does not show even the slightest signs of life, the lamp on the panel may not light up. In this case, the breakdown is determined by the operation of the on-board computer and errors.

You can perform diagnostics by determining the sensor signal level. If the level is low, this indicates:

• No sensor connection;
• Breaks in the circuit;
• Oxidation and breakage of mass in the chain;
• Malfunction of the electronic engine control unit;
• Short circuit or breakage of signal wires;
• A failed mass air flow sensor.

Even if you discover a breakdown, do not rush to purchase a new mass air flow sensor, since this sensor costs from 1.5 to 4 thousand rubles.

In some situations, simply checking and cleaning the air flow sensor can help. Moreover, it is not at all necessary to contact the service center. You can easily complete the task with your own hands.

Examination

There are several ways to check the functionality of the flow sensor. But first you need to determine where the desired object is located.

And our hero is in the engine compartment. Find the air filter pipe there. It is on this that the mass air flow sensor is located, which monitors the air flow passing through the filter. Replacing it is simple - just dismantle the device by removing it from its fasteners and putting a new one in place.

Now regarding the verification.

1. Disconnect the sensor by disconnecting the wiring harness from the connector. Press the latch at the bottom and you'll be good to go. Now start the engine and raise the speed to at least 1500 rpm. By turning off the sensor, the car will perceive this as an emergency condition, so the mixture will be prepared depending on the current throttle position. Drive a short distance. If the car accelerates faster than usual, the mass air flow sensor has definitely failed.
2. Replace the firmware. The original firmware of the electronic control unit is often changed. Therefore, we cannot find out which sensor operation algorithm was prescribed in the case of the first verification method. The throttle valve has a stop; a plate approximately 1 millimeter thick should be placed under it. This will increase the speed. Now the chip with the sensor is disabled. If the mass air flow sensor does not work, the engine will stall. If this does not happen, then the firmware is not original, the steps of the idle speed control are written incorrectly.

Checking with a multimeter

To do this you will have to use a multimeter. And how can I check the functionality of the sensor using this method? Select the DC voltage measurement mode on the device and set the maximum value to 2V.

Separately, you should familiarize yourself with the connection diagram in the case of the VAZ 2114.

IN In some cases, the color may differ, but the sequence always remains the same. This will prevent you from getting confused.

Turn on the ignition with the engine off. The positive probe of the multimeter is connected to the yellow output of the sensor, and the black, that is, positive, goes to the green.

The probes of the measuring device should be inserted through the rubber seals of the connectors without damaging the insulation. The probes should be moistened with the almighty WD 40. Now measure the voltage readings. Compare the result obtained with the data from the table.

Voltage indicator	Air flow sensor condition
	The air flow sensor is in good working order, almost new condition, can serve for a long time
	The sensor is in good condition, although old. There are no complaints about performance
	The air flow sensor is in poor condition, has almost expired and will require immediate replacement

If you install a new sensor, it will initially show readings in the region of 0.996-1.01 V, but over time the voltage will begin to increase. This indicates wear.

Cleaning

Cleaning is one of the most effective ways to bring the mass air flow sensor back to life and ensure its operation for more than one season of operation of your VAZ 2114.

Let's figure out how to clean this measuring device.

1. Using a Phillips screwdriver, loosen the clamp that holds the pipe from the air intake.
2. Remove the corrugation and check if there are traces of oil or condensation inside.
3. Examine the condition of the internal surface of the mass air flow sensor itself.
4. If everything is fine, there should be no traces of contamination.
5. The sensitive component of the sensor often fails due to contamination.

1. To avoid such problems with dirt, it is recommended to regularly replace the air filter according to the owner's manual.
2. Oil may reach the sensor due to an increased oil level in the crankcase due to a clogged oil separator in the ventilation system.
3. The sensor is held on the pipe using two screws.
4. Dismantling is carried out with an open-end wrench. This way you can remove and replace the sensor if necessary.
5. In front there is an entrance on which a rubber sealing ring should be located. It serves to protect against the suction of contaminated, unpurified air. If the seal is missing, it is caught on the filter. As a result, the input grid of the mass air flow sensor will become dirty.
6. Clean the mesh with improvised means. You can use a toothpick or a toothbrush.
7. Replace the seal and return the sensor to its rightful place.

Each method is effective in its own way. But it is best to check the performance of the mass air flow sensor by installing a new sensor in its place. By comparing the car's behavior, you will determine whether replacement or cleaning is necessary.

If you do not have the time or desire to deal with problems with the mass air flow sensor yourself, you can contact a car service center. There, using an oscillogram, they will help you check the condition of the device. But keep in mind that you will have to spend a significant amount of money on diagnostics and replacement at a service station. This is despite the fact that the flow sensor itself can cost 4 thousand rubles.

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.

Signs of malfunction

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 light 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 one. 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.

1. 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:
2. the permissible oil level in the crankcase has been exceeded

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.

Many car enthusiasts have encountered the fact that the sensor of a mass-produced VAZ-2114 failed, but not everyone can carry out diagnostic operations with a minimum set of tools. This article will tell you how to diagnose the MVR using a multimeter.

Video of checking the mass air flow sensor on a VAZ-2114 using a multimeter

DMVR device on VAZ-2114

General view of the DMVR sensor

Before proceeding directly to diagnostics, you need to know the design features and structure of this sensor. Let's look at the diagram of the DMVR device in the image.

DMVR device diagram

Causes of sensor malfunction

The next step before diagnosis is to identify the causes of the malfunction, as well as factors that may influence the mass air flow sensor to fail.

Check Engine icon on instrument panel

The first signal that the car is starting to have problems with the sensor is.

In this case, if you connect to the electronic engine control unit, you can identify the following malfunction: “ Insufficient signal level of the mass air flow sensor ". This is what means that the sensor has failed.

Main features

So, let's look at the main signs of a malfunction of the DMVR:

• Malfunctions of the main power unit , namely: the car stalls at idle.
• , also one of the fundamental factors in the interruption of the operation of this node.
• When changing gears, the car it just stalls.
• . This is due to the fact that the fuel mixture ratio is incorrect.

Now that the signs of a malfunction are clear, we can consider the factors that cause the failure of the DMVR:

• Destruction or breakage of wiring inside the product.
• Loose fixation of the wire block.
• Damage to the inside of the element.
• Oxidation of contacts.
• Wear or burnout due to short circuit.

Often the air flow sensor fails after washing the engine.

Checking the mass air flow sensor using a multimeter

In order to check the mass air flow sensor, it is not necessary to go to a car service center and spend a lot of time and money. To do this, you need a regular tester or multimeter., which can be bought for 300 rubles on the market.

Location of the DMVR sensor

To check the DMVR, you need to know the pinout of the contact group.

So, let's look at the pinout of the mass air flow sensor:

DMVR pinout

1. Contact №5 (in Bosch sensors, as a rule, there is a yellow wire coming from it) - is responsible for supplying an incoming signal from the ECU;
2. Contact №4 (gray or white) - is responsible for powering the device;
3. Contact №3 (green wire) - responsible for grounding;
4. Contact №2 (pink-black) - wire through which information from the sensor is transmitted to the main relay of the fourteenth.

To determine serviceability, you do not need to remove the sensor. The multimeter is set to measure direct current up to 20 volts. Next, follow the step-by-step instructions:

The principle of checking the DMVR sensor

Tester readings (voltage, V)	Air flow sensor condition
0.006 - 1.01	Only new sensors produce this voltage; after several weeks of operation it increases by several hundredths;
1.01 - 1.02	Normal operating voltage of a device in constant operation;
1.03 - 1.04	The device has used up approximately half of its working resource;
1.04 - 1.05	The MAF voltage is in an extremely worn condition, replacement is recommended;
Above 1.05	Such a sensor does not work, or it works but sends distorted signals to the ECU.

Depending on the readings and interpretation, we carry out the appropriate repair operations.

conclusions

Checking the VAZ-2114 mass air flow sensor using a multimeter is quite easy and can be done even by a novice motorist. So, if a car enthusiast is not able to do this with his own hands, he will have to contact a car service.