Can a mass air flow sensor cause high fuel consumption?

DMVR diagnostic process

Air is directly related to the formation of the air-fuel mixture, and accordingly to fuel consumption. When this indicator changes, fuel consumption also changes.

Norms

So, let’s consider what is considered the standard air consumption: the Samara-2 engine, the volume of which is one and a half liters with a normally operating mass air flow sensor at 800-1000 rpm, should consume from 10±0.5 kg of air per hour of operation, and at - 2000 rpm - on average from 19 kg to 21 kg .

A decrease in air consumption leads to a decrease in fuel consumption, but the dynamic properties decrease significantly.

If the situation is the opposite - fuel consumption has increased, then fuel consumption will also increase, and the dynamics will increase accordingly. In this case, in cold weather there will be difficulties starting the power unit. 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.

Reasons for changes in air flow

Clean or change the air filter

Also, it is worth considering the reasons that may cause the air flow in the Samara-2 engine to change:

• DMVR malfunction. This sensor regulates the air supply and the formation of the correct reading of the air-fuel mixture in the engine. The malfunction is eliminated by checking the DMVR or replacing the damaged element. Also, do not forget that it is necessary to regularly clean the sensor.
• A throttle valve that regulates air flow. If the element is jammed or malfunctioning, it may supply too much or insufficient air to the cylinders. The malfunction is often eliminated by cleaning the element.

Even a slightly dirty throttle valve can affect air flow

We learn how to check and clean the mass air flow sensor on a VAZ 2114

To ensure more efficient and stable operation of any modern engine, many different devices are used. One of these is the mass air flow sensor (MAF), in particular, we will talk about VAZ 2114 cars. Read more about the functions, malfunctions, diagnostics and cleaning of the controller below.

What is the VAZ 2114 mass air flow sensor and what functions does it perform? The primary task of the regulator is to create arrogance from air and fuel vapors.

The regulator can measure two interconnected parameters, namely:

• reaction time;
• volume of air used.

In accordance with the information received, the correction device determines the required volume of components to create the mixture. If incorrect data is provided, the mixture will not be able to correspond to the operating mode of the power unit; accordingly, its power may decrease and fuel consumption may increase.

Optimal air flow

If the mass air flow sensor is operational, then when the engine is running at 900 rpm, the volume of air used will be at least 10 kg per hour. When the speed increases to 2 thousand, this figure will increase to approximately 20 kg. If the volume of air at such speeds drops, the dynamics of the vehicle will also decrease, and accordingly, this will lead to a decrease in gasoline consumption.

If these indicators increase, this will also contribute to an increase in fuel volume. If the parameter deviates by 2-4 kg, you should not allow it, since in this case the operation of the power unit may be incorrect.

Causes of malfunctions

The mass air flow sensor can break down not only due to problems in the crankcase ventilation. The ventilation system itself in the VAZ 2114 is dual-circuit; it is responsible for the operation of the internal combustion engine in closed or open throttle mode.

When the damper is closed, gases from the crankcase escape through the line, but some of them remain in the idle line. The gas may come into contact with the MAF resistor on the VAZ 2114, and as a result of resin accumulating on its body, the device may produce incorrect data.

Accordingly, this leads to various malfunctions of the regulator (video author - KOSSS102).

Diagnosis of failure

If the air flow sensor breaks down, the symptoms of the malfunction can be very different. First of all, fuel consumption will increase; another symptom may be floating engine speed.

In addition to these signs of failure, the following can be identified:

• failures in the operation of the power unit;
• slower car acceleration, poor dynamics;
• the power unit can turn off when changing gears;
• decrease in power and increase in gasoline consumption;
• a heated internal combustion engine is more difficult to start;
• the Check light appears on the control panel.

The last symptom may not appear if the controller fails completely. How to check the MAF on your own? Diagnostics consists of identifying the impulse.

If the impulse is low, this indicates:

• possible short circuit or broken wiring;
• regulator failure;
• incorrect operation of the ECU;
• oxidation of contacts;
• that the controller is not connected.

Clogged air flow regulator

Check Features

To understand how the mass air flow sensor is checked, first find the device located in the engine compartment. On VAZ 2114 cars the regulator is located on the air filter line. How to check the sensor yourself?

First, the controller must be disconnected from the network; to do this, press on the wire fastening. Start the engine and let it run for a while. You need to drive the car a little - if it accelerates faster than usual, then this indicates a failure of the controller.

The diagnostic procedure can be carried out by replacing the firmware of the control unit. There is a small stop on the throttle; you need to place a plate under it, its thickness should be about 1 mm, thanks to this it will be possible to increase the speed. Then the power supply to the regulator is also turned off; when the device is operational, the motor should stall (video author - Vanechek 01rus).

Cleaning instructions

As practice shows, cleaning the mass air flow sensor is one of the most effective methods of restoring the functionality of the controller. Therefore, if the sensor breaks down, it is not necessary to change it, especially since such a pleasure today is not cheap. This procedure is necessary because over time it becomes dirty and shows other parameters.

So, how to clean the mass air flow sensor at home with your own hands:

1. You will need a Phillips head screwdriver; use it to loosen the clamp securing the line from the air intake.
2. Next, dismantle the corrugation and visually assess the condition of the system. You may see condensation or traces of engine fluid under the corrugation.
3. Carefully inspect the inside of the controller. If everything is normal with the system, then there will be no traces of leaks or contamination. As practice shows, the sensitive element often breaks precisely due to an excess of contamination. In order not to avoid problems of this kind in the future, it is necessary to periodically replace the air filter. This procedure is carried out in accordance with technical regulations. Engine fluid may enter the controller as a result of an increased level of consumables in the crankcase. Accordingly, this occurs as a result of a clogged oil separator in the ventilation system.
4. The regulator itself is fixed with two bolts on the line. The removal procedure is carried out using an open-end wrench. At this stage, if you are sure that the device has failed, you can replace it.
5. You can see the entrance on which there will be a sealing rubber band designed to protect the device from the suction of dirty air flow. If you do not have a seal, it may have caught on the filter element. Accordingly, this will lead to the regulator input grid being contaminated.
6. Clean the mesh using available materials. To do this, you can use a regular toothpick or toothbrush. After cleaning, the seal can be put back and the regulator can be put back in place.

Sorry, there are no surveys available at this time.

“Proper cleaning of the mass air flow sensor on 2114”

Detailed instructions are given in the video (the author of the video is IZO)))LENTA).

Basic faults

The mass air flow sensor rarely fails and requires repair, but it is important to know what the signs of its malfunction are:

1. Fuel consumption increases. This can be determined by the on-board computer. If the flow meter malfunctions, fuel consumption increases by a liter or more.
2. The car's power decreases.
3. Uneven operation of the power unit. The car either accelerates slowly or picks up speed too quickly.
4. The engine does not start or does not start the first time.
5. Idle speed is floating.

The listed signs do not necessarily indicate a breakdown of the flow meter; the reasons may be the malfunction of other devices, which will require their repair. Therefore, it is necessary to check the serviceability of the flow meter.

What are the malfunctions of the mass air flow sensor in the VAZ-2110

The MAF indicators determine the correct mixture formation of the air-fuel mass in the VAZ-2110. Malfunctions and inaccuracies in the coordinated operation of all components of a single sensor system provoke problems in the operation of the device, and it may also be impossible to start the engine in the car.

Mass air flow sensor VAZ 2114

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.

Useful video

You can learn more about the possibilities of reducing fuel consumption by watching the video below:

Maintaining the proper condition of the car in the future will save the owner from hassle and unexpected expenses. You just need to promptly replace clogged filters and damaged spark plugs, and then increased fuel consumption will bypass your car.

• I was told 4 times
• I said 19 times

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What air flow should be on a VAZ 2114?

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.

What is the real gasoline consumption of VA3 2114?

Today it is a real rarity when a car fully complies with the specifications of the technical documentation. Most often, the manufacturer indicates data obtained during testing of the car under ideal conditions. The actual fuel consumption of almost all modern cars is 1-2 liters higher than the norm. You should not neglect important factors that contribute to increasing the “appetite” of the machine.

These factors are:

1. Vehicle operating conditions.
2. Driving manner and style.
3. The presence of various types of malfunctions.
4. Fuel quality.

High fuel consumption VAZ 2114 injector 8 valves, how much is this in numbers? Most owners of the 8-valve “fourteenth” note consumption in the range of 8.5 – 9 liters in the urban cycle and 7-7.5 liters per 100 km on the highway. This is an average figure that is close to the fuel consumption rate specified by the manufacturer.

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.

Cleaning the sensor

If you observe signs of a malfunction of the mass air flow sensor, then you can try cleaning the device.

By the way, this is the most expensive sensor of all in the line of front-wheel drive VAZ cars. But if yours is broken, don’t rush to change it. There is a small chance of restoring his “health”. For the cleaning process you will need a special liquid that is used to clean the carburetor. Star keys are also useful. Unscrew the clamp, as well as the two “10” bolts. Remove the pipe and take out the sensor. Spray the liquid onto the wire and tube. Work with extreme care, wait until this liquid has completely evaporated and leave the device to dry.

While the device is drying, remove the throttle assembly. You will see plaque inside the throttle assembly. It needs to be removed with liquid. This dirt causes problems with the entire system. Because of it, problems with the mass air flow sensor appear, signs of a malfunction of the VAZ 2115, which bother beginners on automobile forums.

Do not remove the throttle cable. Place the knot on a cloth and treat particularly dirty areas with the liquid. Don't forget to clean the idle air control valve and the space underneath it.

After this, most likely, all signs of problems with the mass air flow sensor will go away, of course, provided that the sensor has no mechanical damage. Therefore, do not wait until you have the first signs of such problems, but take such prevention this coming weekend. It won't take you much time, and your car will truly breathe. You won't recognize your engine. It will start much better, its traction will improve, and you will notice an increase in the power of your engine.

Carry out such preventive maintenance regularly, and your car will thank you.

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;
• Badly ;
• 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.

DESCRIPTION

The MAF sensor (mass air flow sensor) measures the volume of air passing through the throttle body. The ECM uses this information to determine the duration of fuel injection and generate the appropriate air-fuel ratio. Inside the MAF sensor there is a heated platinum wire that is exposed to the incoming air flow. By passing a specified amount of current through the wire, the ECM heats it to the desired temperature. The flow of incoming air cools the wire and the internal thermistor, changing their resistance. To keep the current constant, the ECM varies the voltage applied to specified devices in the MAF sensor. The voltage level appears to be proportional to the air flow rate passing through the sensor, and the ECM uses this level to calculate the intake air volume. This circuit is designed in such a way that the heated platinum wire and the temperature sensor form a bridge circuit, and the power transistor is controlled so that the potentials of A and B remain unchanged, thereby maintaining the set temperature.

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.

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.

Check with a multimeter

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

Subsequence

Wire color

Meaning

Power output

Main relay output

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

The condition is critical, the resource is exhausted. It is recommended to replace it as soon as possible to avoid troubles.

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.

Typical operating parameters of VAZ injection engines.

Here I found useful information on typical parameters. Made essentially as a note to myself.

For many novice diagnosticians and ordinary car enthusiasts who are interested in the topic of diagnostics, information about typical engine parameters will be useful. Since VAZ car engines are the most common and easiest to repair, we’ll start with them. What should you pay attention to first when analyzing engine operating parameters? 1. The engine is stopped. 1.1 Coolant and air temperature sensors (if equipped). The temperature is checked to ensure that the readings correspond to the actual engine and air temperatures. It is better to check using a non-contact thermometer. By the way, one of the most reliable in the injection system of VAZ engines are temperature sensors.

1.2 Throttle position (except for systems with an electronic gas pedal). The gas pedal is released - 0%, the accelerator is pressed - according to the opening of the throttle valve. We played with the gas pedal, released it - it should also remain 0%, while the ADC with a dpdz of about 0.5V. If the opening angle jumps from 0 to 1-2%, then as a rule this is a sign of a worn out valve. Less common are faults in the sensor wiring. With the gas pedal fully pressed, some units will show 100% opening (such as January 5.1, January 7.2), while others such as Bosch MP 7.0 will only show 75%. This is fine.

1.3 MAF ADC channel in rest mode: 0.996/1.016 V - normal, up to 1.035 V is still acceptable, everything above is already a reason to think about replacing the mass air flow sensor. Injection systems equipped with feedback from an oxygen sensor are able to correct, to some extent, incorrect readings of the mass air flow sensor, but there is a limit to everything, so you should not delay replacing this sensor if it is already worn out.

2. The engine is idling.

2.1 Idle speed. Typically this is 800 - 850 rpm with a fully warmed up engine. The idle speed value depends on the engine temperature and is set in the engine control program.

2.2 Mass air flow. For 8-valve engines, the typical value is 8-10 kg/h, for 16-valve engines - 7-9.5 kg/h with a fully warmed-up engine at idle. For the M73 ECU these values ​​are slightly higher due to a design feature.

What is a DMRV?

This device is very necessary in order to determine the volume of air that fills the combustion chambers when the engine is running. The sensor is usually installed after the air filter in the power system.

When driving, the automobile power unit is supplied with 1 volume of fuel, as well as 14 equal parts of air. This prepares the correct fuel-air mixture. This is the key to proper operation of the motor in the most optimal modes for it. For any violation of this ratio, the car owner will observe either increased fuel consumption, or a decrease in the power of the power unit, or both. If you know the signs of a malfunction of the mass air flow sensor, it is easy to identify a breakdown of the device.

The mass air flow sensor is necessary in order to accurately measure the required amount of air. This amount is calculated in the sensor itself and then sent to the ECU, where, based on these data, the required amount of fuel will be calculated.

The more the driver presses the accelerator pedal, the more air enters the combustion chambers. The sensor records the amount and sends a special command to the ECU to increase the volume of injected fuel. If the car is to run or drive more smoothly, then a small amount of air will be needed. This is why you need a mass air flow sensor. It measures the required volumes of air for engine operation with maximum accuracy.

Measuring the volume of air means determining the load that will be applied to the motor. When you press the accelerator pedal, the throttle valve opens and the volume of air received increases.

Sensor device

The sensor itself is a combination of two sensors - control and working, as well as a heating resistor.

View of the flow meter from the grid side.

The sensor is disassembled.

The platinum thread is visible in this photo.

As a result, air flow and temperature are converted into electrical impulses understandable to the ECU. This is a very gentle and accurate device; it allows you to calculate the cyclic filling of the cylinders with air and updates the parameters every 0.1 s.

Mass air flow sensor diagram.

The working body of the sensor is a heated platinum thread. It heats up to operating temperature (from 100 to 1000 degrees), and when air enters, it cools down. The amount by which the filament temperature drops is converted into an electrical signal and, based on this value, the ECU calculates the mass and temperature of the air entering the combustion chamber. And based on this data, it prepares the required portion of fuel. In short - yes.

PURPOSE AND PRINCIPLE OF OPERATION

The VAZ 2114 injection engine is a complex design capable of operating in different load modes. In order to ensure normal operation of the power unit and the optimal amount of gasoline consumed, the car’s electronic brains must determine as accurately as possible the ratio of gasoline and air in the supplied fuel mixture.

To determine the required ratio of the proportions of the fuel mixture, the ECU uses the indicators of various measuring instruments - the main one is the mass air flow sensor.

Let's figure out what this DMRV is and what it is eaten with.

Mass air flow sensor (also known as a flow meter) is a sensor that determines the amount of air entering the car engine. Based on the obtained air consumption indicators, the ECU determines how much gasoline needs to be supplied to the combustion chambers.

The sensitive element of the sensor is represented by a thin platinum thread. During operation of the device, this thread heats up to a temperature of 1000 degrees and is cooled by the flow of passing air. The amount of air passed through is determined based on the temperature to which the sensitive element has cooled. The lower the temperature, the higher the conductivity of the platinum, and the greater the amount of current transmitted to the thread it conducts.

The cost of the sensor is about 2-3 thousand rubles. The products of the German company Bosch have proven themselves well, while the owners of the fourteenth, on the contrary, do not respond entirely positively to the domestically produced mass air flow sensor.

Mass air flow sensor device

Flowmeter design

Knowing the design of the air sensor, you will quickly understand the principle of its operation and understand why a faulty meter cannot be repaired, but only replaced. The device is not difficult to find - it is built into the air duct connecting the filter - air flow purifier with the throttle valve block. The exact location depends on the make and model of the car.

The majority of vehicles in use are equipped with hot-wire or film meters. The difference is in the design of the sensing element; the operating principle remains unchanged. An anemometer flow meter is a housing in which 2 platinum threads are placed - a measuring and a reference. How does the mass air flow sensor function in a car:

1. The controller supplies power to both threads. As they heat up, they change resistance equally.
2. When the engine is running, the first thread is washed by air passing through the throttle and cooled. The stronger the air flow, the more intense the cooling.
3. The electronic unit records the difference in resistance between the measuring and reference threads. Having made the calculation, the ECU determines the mass of passing air and directs the corresponding amount of fuel to the injectors.

Reference. In modern cars with turbocharged engines, mass flow sensors are replaced by absolute pressure meters (MAP) - more reliable devices with a long service life. Manufacturers began to equip new naturally aspirated engines with similar products.

The film measuring device operates on the same principle, only instead of threads, platinum-coated ceramic elements are used. That is why it is quite possible to check the mass air flow sensor, but not to repair it. A burnt thread or damaged coating cannot be replaced, only the entire product.

CHARACTERISTIC SIGNS OF MALFUNCTION

As already mentioned, a working mass air flow sensor on a VAZ 2114 is a necessary condition for the normal operation of the engine of the fourteenth, and if any problems arise with the device, they will certainly affect the functioning of the engine, which you will immediately feel.

The air consumption at idle speed of the VAZ 2114 varies between 8-10 kg/hour; when the engine operates at 3000 rpm, it increases to 29-31 kg/hour. In this case, the optimal ratio of gasoline and air in the fuel mixture is 1 to 15.

If the MAF readings differ from the actual consumption, the amount of gasoline is calculated incorrectly, which contributes to either excessive fuel consumption or problems with the engine.

Signs of a malfunctioning mass air flow sensor:

• First of all, engine malfunctions will begin at idle speed - the speed will begin to float or increase on its own;
• Then the dynamics of acceleration will worsen - the car will stall even when accelerating from a hill;
• Due to the incorrect ratio of gasoline and air, fuel consumption will increase significantly (up to a twofold increase);
• Also, the fourteenth may stall when trying to change gears.

Don’t be fooled by the absence of a lit “Check Engine” indicator on the dashboard, because if the mass air flow sensor does not show any signs of life at all, the light may not light up.

If your fourteenth is equipped with an on-board computer, it will display the error “Insufficient air flow sensor signal level”

It can be caused by various factors:

• weak fixation of the contact block;
• oxidation of the contacts themselves or broken wiring;
• damage to the sensitive element;
• broken internal wires.

No matter what signs of a malfunction of the mass air flow sensor appear, to make a final conclusion about the operability of the device, it is necessary to check it.

The main signs and reasons for the increase in fuel consumption of the VAZ 2114

If it’s summer and you drive on normal roads, but at the same time you notice an abnormal “appetite” of the fuel-injected 8-valve VAZ 2114, then it’s time to conduct a full diagnosis of the car’s condition. Excessive fuel consumption is easy to notice not only by the frequency of visits to gas stations. Often, owners note some oddities in the operation of the engine. Unstable operation of the “heart” of the car is accompanied by black smoke from the exhaust pipe and the presence of popping noises in the muffler or intake manifold.

Black smoke from the exhaust pipe most often occurs due to the formation of an overly rich fuel mixture. This disease occurs due to clogged injectors, faults in the ECU, and low-quality spark plugs.

Gasoline consumption can increase, both for a simple and harmless reason, and in the event of serious malfunctions in the car system. For example, a clogged fuel filter increases the fuel consumption of the “fourteenth” by as much as 2-3 liters. Low tire pressure and non-standard wheel radius also contribute. It has long been a known fact that the larger the radius of the wheel, the more effort must be made to turn it.

OPERATIONAL CHECK

Checking the mass air flow sensor does not require a trip to a service station; if you have a multimeter and an hour of free time, you can do it yourself.

FEATURES OF CHECKING THE MAF WITH A MULTIMETER

Checking the VAZ 2114 mass air flow sensor with a multimeter requires knowledge of the pinout of its contacts, which you can see in the image below.

Figure 1.1: MAF pinout

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

Next, take the multimeter and switch it to DC measurement mode. It is necessary to set the maximum measurement limit to 2 Volts. The check is performed using the following algorithm:

1. We connect the red electrode (-) of the multimeter to contact No. 5, the black electrode (+) to contact No. 3. Thin electrodes of the tester must be inserted under the rubber contact seals so that they do not damage the protective coating;
2. Turn on the car ignition (do not start the engine);
3. We look at the multimeter readings.

Rice. 1.2: Correct connection of multimeter probes

HOW TO CHECK THE OPERATION OF THE MAF WITHOUT A MULTIMETER

If, due to the lack of a tester, you cannot check the device using the method described above, there is only one test option left - remove the air flow sensor and see how the car behaves without it.

Dismantle the device or simply turn off the power going to it, start the engine and crank it at 1500 rpm. Start moving. In this case, the ECU puts the fourteenth into emergency mode, in which the fuel mixture is supplied based on the current throttle opening angle.

If, when driving without a mass air flow sensor, you felt that the car literally came to life - it began to pick up speed better when accelerating, problems at idle disappeared, most likely the air flow sensor on the VAZ 2114 is faulty and needs to be changed.

However, a situation is possible in which the cause of the problem is not a failed mass air flow sensor, but incorrect firmware of the ECU itself.

The likelihood of this increases if you took the fourteenth from your hands, since previous owners often do not bother to mention their experiments with the electronic controller.

To check the accuracy of the IAC (idle air regulator) and mass flow sensor control algorithm specified in the ECU firmware, it is necessary to install a spacer in the throttle valve, this is necessary to increase engine speed. A thin metal plate no more than 2 mm thick can be used as a spacer.

REMOVAL AND REPLACEMENT

If checking the mass air flow sensor shows that the device is not working correctly, do not rush to throw the part into scrap. It may be possible to revive it by cleaning the contacts. A separate article is devoted to this procedure on our website.

However, if all else fails, you should go to the store for a new device - keep in mind that the mass air flow sensor is a rather expensive part, the cost of which varies between 2-3 thousand rubles.

To replace, we need a flat-head screwdriver and a 10mm wrench.

Replacing the mass air flow sensor is carried out according to the following algorithm:

1. Turn off the ignition, open the hood and remove the “-” terminal from the battery;
2. We determine where the mass air flow sensor is located. It is not difficult to find; in the engine compartment you will see a plastic air filter block, on the rear rear part of its housing there is a mass air flow sensor. It is attached to the air filter pipe;
3. Remove the metal clamp that connects the corrugated air supply hose to the device;
4. We tighten the corrugated hose;
5. We take out the contact block. There is a button on the bottom of the plug that must be pressed (to disconnect the spring wedge), after which the block can be easily pulled out;
6. Using a 10mm wrench counterclockwise, unscrew the first fixing bolt, then the second, it is located on the bottom of the device body;
7. We remove the mass air flow sensor.

Rice. 1.3: Location of the mass air flow sensor

Installation of a new part is carried out in reverse order. This technique is applicable not only for the fourteenth, but also for the VAZ 2115 and VAZ 2113.

How much does a new sensor cost?

Of course, car parts are not cheap, but if necessary, they must be purchased in order for the vehicle to work properly.
The sensor should be purchased only in specialized stores where there is a guarantee, and where you can actually get competent advice. This spare part costs around 350 rubles. As a rule, such options are very reliable and durable. It makes no sense to buy cheaper ones, since their characteristics are in no way inferior to those that cost 350. It’s not worth buying cheaper ones, because these are mostly Chinese parts that are short-lived and of poor quality. If you find it difficult to choose, then ask the seller which sensor is better to choose. Basically they are all similar, the only difference is the price. Please note that this part can also be purchased online. The main thing is not to be cheap, but also not to spend all your money on one spare part. As we can see, any part of the machine becomes unusable over time, so it needs to be replaced. As for the idle speed sensor, this device also needs to be replaced from time to time for the accuracy of the indicators. Quite often, due to a faulty sensor, a car begins to have problems with the engine, the speed deteriorates, etc. With such problems, it is quite dangerous to drive a car, since there is no guarantee that the engine will work without “whims,” and on the road this is very dangerous . You shouldn’t risk your most valuable assets; it’s better to send the car in for repairs or fix it yourself. A car, like any other device, must be used carefully and repaired as needed, then it will serve for a long time and reliably.

DMRV of VAZ 2114 car

VAZ 2114 cars were equipped with several types of engines: 8 valves of 1.5 liters and 1.6 liters, as well as 16 valves of 1.6 liters. Until 2005, January 5 series ECUs were installed on the motors, then the manufacturer updated the controllers. Since 2006, these machines have been equipped with a January 7 series ECU, or imported analogues of BOSCH 7.9.7. Why do you need this information? Depending on the version of the ECU, mass air flow sensors on the VAZ 2114 were of different types. This causes some difficulties when replacing the sensor, but detailed information can be found in the car's passport.

• Air flow sensors of the 004 series were installed on early versions of cars.
• Then an updated mass air flow sensor was introduced for the VAZ 2114, series 037. The measuring channel on it was modified to reduce air flow pulsations. The new flow meter with modified characteristics is fully compatible with old ECUs with an oxygen sensor, so the replacement did not lead to changes in calibrations in the fuel-air mixture formation system.
• After switching to the January 7 series and BOSCH 7.9.7 controllers, we also had to change the air flow sensor on the VAZ 2114. The new version with index 116 is produced with an updated design. The calibration of the sensor has also been updated, so there is no backward compatibility.

The BOSCH 116 air sensor has many analogues, including the Russian Itelma and Avtel.

Information: There is an opinion among VAZ 2114 owners that the air flow sensor of the 116 series is better than the 037, and it can be replaced to increase engine output. In fact, this is not the case; the calibration of the mass air flow sensor is developed for a specific motor and is taken into account when programming the ECU.

As an example, the graph in the illustration:

Obviously, when the air flow rate is more than 100 kg per hour, the voltage that the VAZ 2114 series 116 air sensor produces changes by 0.2 volts. When the data is read by the engine controller, this makes a significant correction in the proportions of the fuel mixture.

How does the VAZ 2114 mass air flow sensor work?

A modern mass air flow sensor (also known as MAF in English) uses sensitive sensors and a special calculation algorithm to compare the resistance readings of two thermistors. One of them is a reference value, its value is constant. The second (made of platinum-iridium wire) is forcibly heated. The incoming air flow cools the wire, the resistance changes, and to equalize it with the reference, a larger heating current is required. It is the difference in current strength (in this design, voltage is measured using the Ohm's Law formula) that provides information to the ECU.

The measurement accuracy is 1/100 volt, so the slightest malfunction of the mass air flow sensor instantly affects the quality of engine operation.

VAZ 2114 signs of flow meter malfunction

In addition to the indicator light on the Check Engine, there are symptoms that even an inexperienced driver will notice:

1. Unstable engine operation at idle speed: the malfunction manifests itself most clearly when the engine is not warmed up. After starting, the revs fluctuate, and when the accelerator pedal is pressed sharply, the engine stalls.
2. With a sharp release of gas, the speed does not decrease, but remains at around 2-3 thousand for some time.
3. Even with a warm engine, there is a noticeable decrease in power. When fully loaded, a lower gear is required; the car does not pull uphill and accelerates slowly on the highway.

How to independently check the VAZ 2114 MAF sensor the “old-fashioned way”? The technique is as follows:

• you need to remember the sensations of the engine running on a familiar route with different modes: uphill, acceleration, etc.;
• turn off the engine, remove the negative terminal from the battery and disconnect the mass flow sensor connector located on the side of the brake fluid reservoir;
• start the engine and travel along the same route.

If the engine behavior has noticeably worsened, then the failure is not related to the flow meter. If you do not feel the difference, that is, the motor works the same with and without the sensor, then an in-depth check of the mass air flow sensor is required.

How to check the MAF sensor on a VAZ

The most reliable way is to use a diagnostic scanner (at least at the ELM-327 level). We connect to the OBD port and look at the flow meter performance indicators on the computer.

If you don’t have a scanner, you can take the basic parameters with a multimeter. To diagnose and repair the VAZ 2114 mass air flow sensor with your own hands, you need to know the pinout of the contacts.

For example, consider a contact block for a VAZ 2114: a modern 8 or 16 valve engine, BOSCH mass air flow sensor (or its equivalent) version 116.

1. We don't need contact No. 1; this is an air temperature sensor.
2. Contact No. 2 - 12 volt power supply. If the on-board voltage regulator malfunctions, the air flow sensor may malfunction.
3. Contact No. 3 - ground.
4. Contact No. 4 - power supply for the mass air flow sensor electronics, an important parameter, the voltage must be stable.
5. Contact No. 5 is the same “floating” voltage with which the ECU calculates the volume of air passing through the intake manifold.

The supply voltage is checked with the block disconnected. We turn the ignition key, but do not start the engine. With respect to ground, we measure the voltage at contact No. 2 (12 volts) and contact No. 4 (5 volts). This indicates the serviceability of the ECU and the integrity of the wires and contacts.

Checking the signal voltage on pin No. 5 is carried out with the connector connected, with the ignition on (do not start the engine!).

• voltage is within 0.99-1.02 volts - the sensor is working;
• voltage within 1.03-1.05 volts - replacement will be required soon;
• more than 1.05 volts - the mass air flow sensor does not operate normally.

Where is the DMRV located?

The sensor is located between the air filter and the air supply hose (pictured No. 13).

Catalog numbers of mass air flow sensor on LADA cars:

• Lada Priora, Kalina and Niva 4x4 - 21083-1130010-20.
• Lada Granta and Kalina 2 - 11180-1130010-00.
• Lada Vesta, Largus and XRAY - no mass air flow sensor. Modern VAZ engines (21127, 21129, 21179) and Renault engines (K7M and K4M) do not have a mass air flow sensor; instead, an absolute pressure sensor (APS) and an air temperature sensor (ATS) are installed.

Prevention of breakdowns and cleaning of the air flow sensor of the VAZ 2114

The flow meter sensor is located in a vulnerable place: exposure to temperature changes, moisture, dust.

Precision electronics located in the measuring channel fail when foreign objects enter.

• untimely replacement of the air filter;
• the use of so-called “zero” filters;
• loose connection of the mass air flow sensor with the air duct flanges;
• moisture entering the air intake;
• Debris left in the ductwork or filter housing after repairs and maintenance.

How to clean the mass air flow sensor if contamination does not render it inoperable

The sensor must be removed, the protective nets removed, and blown with clean compressed air. If there is dried dirt or oil stains, washing with special means for mass air flow sensor is required. Of course, it is necessary to clean the air duct itself with the filter housing.

In most cases, such prevention brings the flow meter back to life.