The mass air flow sensor (MAF for short) shows how much air is filled in the cylinders when the engine is running. The mass air flow sensor is connected to the electrical harness of the 6-pin block and is located in the space between the air filter and the throttle valve. It is needed to measure the load on the engine and to ensure that fuel is supplied in the required quantity (to monitor this process, you just need to determine the mass of incoming air).
DMRV VAZ 2114
The MAF is of wire (thread) and film type; the fundamental difference is that for the wire type MAF the sensitive element will be a platinum wire, and for the film type there will be a film on which the measuring platinum resistor is attached. Regardless of the type, the mass air flow sensor tends to become dirty (platinum elements become covered with dust and do not work properly). Let's figure out how to clean the mass air flow sensor one by one.
The main reason for contamination of the air flow sensor is the condition of the air filter! If it is not good, then it begins to let in grains of dirt and dust with the air flow, which settle on the sensitive element of the sensor.
Cleaning the air flow sensor is required if:
- At idle the engine runs intermittently,
- The idle speed is unrealistically off the charts,
- When accelerating, it “stutters” (jerks or runs intermittently),
- Benz is consumed in large quantities,
- You basically can't start.
It also happens that the sensitive element itself is fine, but the connection between the sensor and the throttle module is malfunctioning (the connecting hose may crack). And this is a completely different story. Also, the controller may issue a check engine, which may indicate the same breakdown in the sensor connection circuit (or may indicate a completely different breakdown).
Every owner of a Russian car understands that, despite the obvious signs of a malfunction in a particular part of the car, these signs can relate to any other malfunction. Therefore, trust the signs, but check with specifics.
DMVR device on VAZ 2114
The overall design of the sensor consists of two filaments made of a platinum-based alloy. The threads are heated by electric current, with one being the working thread and the other being the control thread. The working element is located in the air flow supplied to the engine, which cools the part. As the temperature of the filament changes, resistance increases or decreases. The data is compared with the parameters of the control element, and based on this, the amount of air passed is automatically calculated.
On later VAZ 2114 models, thermistors began to be used, which have increased durability and measurement accuracy. This is exactly the sensor that is used on the VAZ 2114.
Where is the mass air flow sensor located?
The mass air flow sensor on the VAZ 2114 is located in the air duct located behind the air purification filter. A wiring harness is connected to the sensor, ending with a plug.
Installation location of the air flow sensor on the VAZ 2114 engine
Sensor design features
The VAZ 2114 can use mass air flow sensors of domestic and imported origin. The design of the devices is the same and corresponds to the diagram below.
Design of the air flow sensor VAZ 2114
The DMRV includes:
- 1 — block for connecting the wiring harness;
- 2 — sensor operation controller;
- 3 - measuring element;
- 4 — outer body;
- 5 — metal protective mesh;
- 6 — guide deflector;
- 7 — fastening the sensor body to the body;
- 8 — direction of air flow.
Functions of mass air flow sensor
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.
DMRV 2114 device diagram
What is the optimal air flow for VAZ 2114 cars?
The amount of air required to form the mixture depends on the speed:
- at idle speed (850-950 rpm) - 9.5-10.5 kg of air per hour;
- at medium speed (2000 rpm) - 19-21 kg of air per hour.
Reducing the air supply leads to a leaner mixture, and increasing it leads to a richer mixture. Small deviations in measurement accuracy have little effect on the operation of the engine, but with errors of 2-3 kg, the engine begins to operate unstably. Some control units compensate for measurement inaccuracies based on data from other sensors. For example, the January 5.1 block additionally adjusts the mixture composition based on the signal from the lambda probe.
The main causes of failure of the mass air flow sensor
The most common causes of sensor failure are:
- dust ingress;
- oil contamination;
- short circuit of the wiring due to damage to the insulation or plug;
- mechanical damage to active elements.
A common cause of incorrect operation of the mass air flow sensor is the failure of electronic components, which increases the sensor’s response time to changes in air flow. A working sensor monitors changes at a speed of 0.5 ms, and if it breaks down, the response time increases by 20-30 times. The defect is detected only by recording the operation graph with an oscilloscope. Such a sensor cannot be repaired; it must be replaced with a new one.
What factors disable the mass air flow sensor?
Factors causing failure of the air flow sensor:
- Dust may be caused by improper installation of the sensor on the filter, which causes the sealing ring to become distorted. With this defect, a thin coating of contamination will be present on the sensor input grid. Another cause of dust is a clogged air filter, so regular maintenance will prolong the life of the air flow sensor.
- Oil is thrown onto the sensor if the level in the crankcase is high or if the oil separator in the ventilation system is clogged. An additional negative factor is engine wear, which causes lubricant to actively enter the crankcase ventilation.
- Contact with sharp objects on the insulation, oiling. Such impacts are the result of careless repairs.
- Damage to the sensor is possible during vehicle maintenance (impacts to the body) or during improper cleaning of the active part.
Cleaning instructions
You can clean the sensor in a garage; no difficulties will arise. Depending on what kind of car you have, the process for removing the sensor may vary.
We will look at an example of removing an element from a VAZ car of the 10th family:
- You must immediately turn off the ignition and remove the negative terminal from the battery.
- Then find the location where the sensor is installed.
- After this, disconnect the connector from it.
- There is a pipe connected to the device; it is necessary to remove it.
- Using a wrench, unscrew the screws securing the device to the air filter housing.
- It is necessary to remove the sensor from the corrugation. On the ten, in order to perform dismantling, you will need an asterisk key.
- Unscrew the screws, and then remove the sensor itself from the seat.
If after removal you notice that there is a deposit of oil on the element, you need to clean the housing of it. To do this, you must use any tool described earlier. Cleaning must be non-contact.
How to restore the mass air flow sensor?
The optimal solution for problems with the mass air flow sensor is to replace the faulty sensor with a new one. But since the cost of the device is about 2500-3900 rubles, many owners are trying to “revive” the old part.
There are four recovery methods:
- installation of additional resistance;
- blocking part of the air supply channel to the thermistor with aluminum tape;
- updating the engine control unit firmware;
- washing the sensor body and housing from dirt.
Installing additional resistance
Additional resistances are installed in the circuit connecting the sensor to the control unit. When an electric current passes, the voltage decreases, which can be brought to the required limits. The resistance value is selected experimentally. Most often, a 1 kOhm resistor is soldered to the yellow wire and a 15 kOhm element to the green wire.
Blocking part of the air supply channel
The repair principle is based on partially cutting off the air supply to the thermistor. Due to this, less intensive cooling is ensured and it is possible to bring the voltage value to the state of a working device. The cross section is selected experimentally with voltage monitoring using a multimeter. In some cases, owners block the supply channel by 70-80%. Aluminum tape is used for gluing.
Correcting the firmware of the engine control unit
An adjustment means a change in the calibration or operating schedule of the mass air flow sensor stored in the unit’s memory. The dependence graph is constructed in such a way that at a sensor voltage of 0.996 volts, the flow rate is considered equal to zero. But if the sensor fails and the starting voltage is 1.055 volts, then the control unit considers the air supply to be 1.8 kg when the engine is not running. Changing the graph using the MAF Corrector utility will allow you to set the flow rate to 0, which will improve engine performance. This method can be recommended to owners who are well versed in the control unit software.
Do-it-yourself cleaning of the air flow sensor
The air volume sensor is cleaned after it is detected that it is not working correctly. The procedure is performed by partially disassembling and removing the device body with active elements. At the same time, the body is washed and cleaned from remaining leaves and dirt deposits. In many cases, washing the air flow sensor on a VAZ 2114 does not help restore the device’s parameters.
Mechanical methods of cleaning the mass air flow sensor on the VAZ 2114 are prohibited, as is blowing dust with compressed air.
What products should be used to clean the sensor?
To clean sensors, there are special liquids supplied in pressurized aerosol cans. An example of such a product is a special air flow sensor cleaner Luftmassensor-Reiniger from Liqui Moly. There are similar liquids from other manufacturers. You can wash the sensor with a mixture of 70% isopropyl alcohol and 30% distilled water, after warming the device to 60-70 ºС with a hair dryer.
When washing the mass flow sensor it is prohibited:
- try to clean the sensor with cotton balls, hard objects and brushes;
- use household cleaning products;
- Use carburetor cleaners based on acetone or ether.
Is it possible to clean the air flow sensor with carburetor cleaner?
It is not recommended to use carburetor cleaners for electronic sensors! The chemicals contained in these products can cause irreversible damage to sensitive elements. However, the use of such compositions for cleaning mechanical flow meters is not excluded. However, here too it is better to use specialized substances, for example, budget cleaners offered by the Kerry brand.
It is necessary to warn owners of cars equipped with similar sensors against other errors:
- Cleaning with more active solvents: this may cause deformation of the plastic parts of the sensor itself and its housing.
- Using cleaner brands not recommended by the vehicle manufacturer.
- Cleaning the mass air flow sensor with products that are used to clean the throttle body.
- Reinstall the unit that has not dried after treatment.
A clean sensor can restore 4 to 10 horsepower to the car, which is well worth the time and expense of cleaning. It is recommended to perform such prevention once a year.
Video “Cleaning the air flow sensor with your own hands”
The secrets of cleaning the sensor with your own hands are revealed in a video filmed for the Avtogarazh channel.
VAZ 2115, a 2012 car, has recently begun to “eat” an unrealistically large amount of fuel - up to 13 liters in the city, which is clearly above the norm. The engine speed constantly drops, especially when accelerating; at idle the speed is also unstable - it stalls or holds up to 3000 rpm. At speed when you walk, the car jerks sharply. I read various information on the Internet, I am inclined to believe that it is the mass air flow sensor that is acting up. I also read that he can be brought back to his senses, albeit for a short time, but I’m wondering how to clean the air flow sensor of a VAZ 2115? What is needed for this? Is carburetor cleaner suitable or not? Thanks for answers.
Well, first of all, you need to disassemble the DMRV. It’s better to measure the voltage on it and find out whether it’s dead or not. I cleaned it and it didn't help
Warm vodka or alcohol.
Throw away the chip, if an internal combustion engine behaves better, then it’s definitely a diesel engine. In general, no one canceled the diagnosis.
Yes, it will do, they usually clean it with it, only the throttle body, not the air flow sensor
It’s better to buy a new sensor, it costs a penny
I cleaned it to no avail, bought a new one and everything became fine
Spark plugs also affect consumption if they are old.
Try it on, if it exceeds the norm and it is clean, then there is no point in washing it against the wall, but if there is soot in it, dirt, oil, then there is no point in washing it
Measure the voltage on it, maybe it’s not the culprit
take readings of both the air flow sensor and fuel pressure! and the explosive wires can still be replaced!
Very similar to my problem, sometimes everything was fine, and sometimes it started to drizzle, the air flow sensor showed normal, but experimentally I found out that sometimes it works, sometimes it doesn’t, the problem was solved by replacing the air flow sensor
Installing a new one, cleaning the air flow sensor almost never helps, in most cases it only gets worse
Check for air leaks and then drip further.
Go for diagnostics, otherwise you won’t have enough money to change all the sensors in order
Pure drinking alcohol, technical leaves a film when weathered. If you decide to clean it.
Make a diagnosis and don’t guess.... There are a lot of sensors, why this could be... And the MAF is dismountable, clean it with carburetor cleaner
you can clean it with anything - if you're lucky, you'll resurrect it for a couple of months. Well, you can’t make it worse for him, although some are lucky. We wrote and wrote about this in detail.
Road transport is constantly being improved. All modifications made to the design of the car are aimed at improving various indicators - increasing power, reducing fuel consumption, improving aerodynamic performance and the level of overall comfort.
This is what the new mass air flow sensor looks like
One of the main improvements related to reducing fuel consumption was the transition from the use of a carburetor power supply system in favor of an injection system.
The use of a system in which the fuel supply is strictly metered for the operation of the power plant in different modes makes it possible to reduce consumption while ensuring the maximum possible output of power from the power unit.
But in a carburetor system, the system is technologically simpler, since the operation of the main element of this system, the carburetor, is performed mechanically, which ensures high reliability. Also in this power system, the air-fuel mixture is formed in the carburetor and enters the cylinders due to the vacuum created by the pistons.
The injection system is technically more complex. The working mixture is already formed in the cylinders, and the components of the mixture are supplied to them separately. Air, one of the elements of the mixture, is supplied due to vacuum, but fuel is forced into the cylinders by injectors.
The electronic control unit is responsible for the required amount of fuel required to be supplied to the cylinders. But in order to correctly dosage, the control unit must know such parameters as the position of the crankshaft and its rotation speed, the amount of air entering the cylinders, the amount of air remaining in the exhaust gases, and the position of the throttle valve. These parameters for calculating the amount of fuel supplied are met by sensors installed in certain elements of the power plant.
Signs of a malfunctioning mass air flow sensor
The performance of the mass air flow sensor plays a significant role in the correct formation of the air-fuel mixture. Therefore, its malfunctions lead to disruption of the installation or, in some cases, the inability to start the motor.
The failure and failure of this sensor can be identified by the following signs:
- the “Check engine” signal comes on;
- increase in gasoline consumption;
- power drop;
- decreased dynamics of speed gain;
- difficulty starting or inability to start;
- floating speed in idle mode.
But such signs are not only a signal that this sensor is broken; there may be other reasons. Therefore, it is necessary to determine whether it is really the mass air flow sensor that is “jamming up”.
Checking the air flow meter
One way to check the air flow sensor
There are several ways to detect a malfunction of this sensor. The easiest way is to disconnect the power supply from the sensor while the engine is running. After the chip is turned off, the control unit goes into emergency mode, in which fuel dosage is carried out according to the readings of the throttle position sensor. In this case, the idle speed will begin to increase to over 1500 revolutions, although not always; some injection systems do not increase the speed.
With the flow meter turned off, you need to drive the car. If the performance of the power plant has improved, most likely there are problems with the mass air flow sensor.
Something else useful for you:
Video: Demonstration of a faulty mass air flow sensor on Kalina, Priora, Grant, VAZ 2110-2112, 2114-2115
Some sensors can be checked using a voltmeter or multimeter with high precision settings. The measuring device is connected with a “positive” probe to the MAF signal wire (usually the far right wire), and with a “negative” probe - to the ground wire of the sensor. Then you need to turn on the ignition, but do not start the power plant. A working sensor should have a voltage between 0.9 and 1.4 V. The readings above indicate a malfunction of the mass air flow sensor.
Very often the failure is caused by contamination of the working elements of the sensor. Therefore, a visual inspection can also indicate a malfunction.
If the working elements of the mass air flow sensor are noticeably heavily soiled, this is most likely the cause of problems with the operation of the power plant. But restoration work can be done with sensors based on a pitot tube. They can be removed from dirt by washing with a carburetor cleaning spray.
Why do you need a mass air flow sensor and how does it work?
A car engine is a very complex device, consisting of many components, the operation of which is ensured by several systems, an on-board computer and special sensors.
In order for the VAZ engine to function flawlessly and consume the optimal amount of fuel, the exact proportion of air and gasoline is extremely important. The ratio is adjusted by the electronic control unit, which, in turn, receives information from several sensors, the main one of which remains the mass air flow sensor. In another way, this device is called a flow meter. It determines the volume of air entering the engine. Based on the sensor readings, the on-board computer regulates the gasoline supply.
The main working element of the mass air flow sensor is the finest platinum wire. When you turn on the engine, it heats up to 1,000 degrees. The passing air cools the thread. Temperature directly affects the conductivity of the metal mentioned - the colder it is, the higher the indicator. Based on heating, the controller judges the intensity of air supply.
Replacing the sensor
Removing the mass air flow sensor
If the check indicates a malfunction of the mass air flow sensor, it is replaced, since they are irreparable. Replacing it is very simple. Using an example, we will look at replacing a sensor on a VAZ-2110.
All replacement work is carried out with the ignition off. First, the chip with the wires going to the sensor is disconnected from the sensor.
Then you need to loosen the clamp securing the inlet pipe to the filter, after which the pipe is disconnected from the filter.
Using a 10mm wrench, unscrew the two bolts that secure the sensor. Now the mass air flow sensor can be removed from its seat.
Here you can learn how to remove the crankshaft pulley.
In this article you can learn how to replace the cabin filter in a car.
Before installing a new sensor in a seat, it is important to check the tightness of the sealing ring, otherwise, if the density is insufficient, there is a possibility of air leaking in, not cleared of impurities, from the outside. And this can cause rapid damage to the sensor.
After checking the seal, the mass air flow sensor is put in place and secured with bolts. Next, put the pipe in place and connect the chip with wires.
The final stage is to check the restoration of normal operation of the power plant.
Liqui Moly
How to clean the MAF sensor? One option is cleaning fluid from Liqui Moly. The company is known to many car enthusiasts as a manufacturer that makes only high-quality products for cars. In addition, the ratio between reliability and price is at an optimal level. As for the use of liquid for cleaning the mass air flow sensor, most vehicle owners have already become convinced of its effectiveness. This has not been proven by a single procedure. And if the sensor is in working condition, then even after cleaning it will last no less.
The liquid can be used for both diesel and gasoline engines.
