Any complex electronic sensor is quite expensive. Therefore, when, for example, a mass air flow sensor fails, car enthusiasts strive to minimize repair costs. The fact that an engine without a flow meter will not work is beyond doubt. Numerous experimenters in disabling the sensor predictably fail, although I tell stories about the successful “improvement” of the motor. And yet, is it possible to bring a “tired” flow meter back to life if purging and cleaning with the most modern means did not help? Is the notorious fake VAZ air flow sensor on sale, or does it need to be done with your own hands?
We recommend remembering the proverb “the miser pays twice” before using your “savvy”, because often dubious and small savings lead in the future to higher costs that arise due to this very saving.
Imagine a situation where the test voltage (ideally 1 ± 0.02 V) does not correspond to the norm?
Information: The functionality of a faulty air flow sensor can only be restored by increasing the voltage at the ADC output. If the flow meter shows no signs of life (no voltage), it is impossible to deceive the ECU.
How to make a fake MAF sensor
Any complex electronic sensor is quite expensive. Therefore, when, for example, a mass air flow sensor fails, car enthusiasts strive to minimize repair costs. The fact that an engine without a flow meter will not work is beyond doubt. Numerous experimenters in disabling the sensor predictably fail, although I tell stories about the successful “improvement” of the motor. And yet, is it possible to bring a “tired” flow meter back to life if purging and cleaning with the most modern means did not help? Is the notorious fake VAZ air flow sensor on sale, or does it need to be done with your own hands?
We recommend remembering the proverb “the miser pays twice” before using your “savvy”, because often dubious and small savings lead in the future to higher costs that arise due to this very saving.
Imagine a situation where the test voltage (ideally 1 ± 0.02 V) does not correspond to the norm?
Information: The functionality of a faulty air flow sensor can only be restored by increasing the voltage at the ADC output. If the flow meter shows no signs of life (no voltage), it is impossible to deceive the ECU.
Briefly about the renovation
As a rule, MAF sensors that have become unusable cannot be repaired, except in cases where they require washing and cleaning.
In some cases, it is possible to repair the volumetric air flow sensor board, but this process will not prolong the life of the device for long. As for the boards in film sensors, without special equipment (for example, a programmer for a microcontroller), as well as skills and experience, it is pointless to try to restore them.
This project appeared due to the reluctance to buy a part that had been in use for about 30 (thirty) years for a quite considerable amount of 3,000 - 5,000 rubles. We can say that this will be a test of the pen in circuit design and programming of microcontrollers. If you're interested, see the continuation below the cut.
Be careful there are a lot of photos!
So, we start propping up the bikes with crutches.
Input data
BMW E30 coupe 1986 with M10B18 engine (4 cylinders, 1.8L, injection):
How to trick a broken mass air flow sensor using a resistor
Let's consider the “restoration” option using the example of a VAZ 2110. After an unreasonable increase in fuel consumption, you decide to check the mass flow sensor with a multimeter. The readings at rest significantly exceed the ideal “no higher than 1.02 V” and even the acceptable “1.05 V”.
Accordingly, the engine sees a lean fuel-air mixture and adds more gasoline to the ratio. The result is an increase in consumption without an increase in power.
How to reduce the voltage at the ADC output of a flow meter? We know that based on the calibration of the mass air flow sensor in the electronic engine control unit, each value in volts corresponds to the volume of air in kg/hour.
How to reduce tension? Any novice electrician will tell you that you need to add resistance (additional resistor). Of course, it will not be possible to guess (or even calculate) the required value, so it is better to use a variable resistor in the range from 1 kOhm to 2 kOhm. Old Soviet SP-1 alternators are suitable. They will not fall apart from moisture or temperature under the hood.
The resistor is connected to the break in the wire running from contact No. 5 of the VAZ mass air flow sensor to the engine ECU controller.
Important: All work on the wiring harness is performed with the battery disconnected.
After connecting, we check the flow meter at rest:
- connect the multimeter to contacts No. 3 (ground) and No. 5 (ADC signal) of the mass air flow sensor connector;
- turn on the ignition without starting the engine;
- By tightening the variable resistor regulator, we achieve a value of 1 volt.
After this, it is necessary to mechanically secure the resistor so that it does not break during movement. We carry out a test drive and make sure that gasoline consumption is reduced.
Functionality check
Before diagnosing the mass air flow sensor, you need to know the symptoms that allow you to determine the degree of performance of the MAF (abbreviation for the English name of the device) sensor in the car. We list the main symptoms of a malfunction:
- The consumption of the fuel mixture has increased significantly, while at the same time acceleration has slowed down.
- The internal combustion engine idles with jerks. In this case, a decrease or increase in speed may be observed in idle mode.
- The engine does not start. Actually, this reason in itself does not mean that the flow meter in the car is faulty; there may be other reasons.
- A message appears about a problem with the engine (Cheeck Engine)
Example of the "Cheeck Engine" message displayed (marked in green)
These signs indicate a possible malfunction of the mass air flow sensor; in order to accurately determine the cause of the failure, diagnostics must be performed. It's easy to do it yourself. Connecting a diagnostic adapter to the ECU (if this option is possible) will help to significantly simplify the task, and then determine the serviceability or malfunction of the sensor using the error code. For example, error p0100 indicates a fault in the flow meter circuit.
Finding an error using a diagnostic adapter
But if you need to carry out diagnostics on domestic cars manufactured 10 years ago or more, then checking the mass air flow sensor can be carried out in one of the following ways:
- Testing while moving.
- Diagnostics using a multimeter or tester.
- External inspection of the sensor.
- Installation of a similar, known-good device.
Let's consider each of the listed methods.
Testing while driving
The easiest way to check is by analyzing the behavior of the internal combustion engine with the MAF sensor disabled. The algorithm of actions is as follows:
- You need to open the hood, turn off the flow meter, close the hood.
- We start the car, and the internal combustion engine goes into emergency mode. Accordingly, a message indicating a problem with the engine will appear on the dashboard (see Fig. 10). The amount of fuel mixture supplied will depend on the position of the remote control.
- Check the dynamics of the car and compare it with what it was before the sensor was turned off. If the car has become more dynamic and power has also increased, then this most likely indicates that the mass air flow sensor is faulty.
Note that you can continue driving with the device turned off, but this is highly not recommended. Firstly, the consumption of the fuel mixture increases, and secondly, the lack of control over the oxygen regulator leads to increased pollution.
Diagnostics using a multimeter or tester
Signs of a malfunction of the mass air flow sensor can be identified by connecting the black probe to ground, and the red probe to the sensor signal input (the pinout can be found in the device data sheet, the main parameters are also indicated there).
An example of measuring the voltage on the mass air flow sensor in a VAZ 2114 car with a multimeter
Next, we set the measurement limits to 2.0 V, turn on the ignition and take measurements. If the device does not display anything, you need to check that the probes are connected correctly to ground and the flow meter signal. Based on the readings of the device, you can judge the general condition of the device:
- A voltage of 0.99-1.01 V indicates that the sensor is new and working properly.
- 1.01-1.02 V – used device, but its condition is good.
- 1.02-1.03 V - indicates that the device is still operational.
- 1.03 -1.04 the condition is approaching critical, that is, in the near future it is necessary to replace the mass air flow sensor with a new sensor.
- 1.04-1.05 – the device’s resources are almost exhausted.
- Over 1.05 - a new mass air flow sensor is definitely needed.
That is, you can correctly judge the state of the sensor by the voltage; a low signal level indicates an operational state.
External inspection of the sensor
This diagnostic method is no less effective than the previous ones. All that is necessary is to remove the sensor and assess its condition.
Inspect the sensor for damage and fluid
Characteristic signs of a malfunction are mechanical damage and liquid in the device. The latter indicates that the oil supply system to the engine is not adjusted. If the sensor is very dirty, the air filter should be replaced or cleaned.
Installing a similar, known-good device
This method almost always gives a clear answer to the question of the sensor’s performance. This method is quite difficult to implement in practice without purchasing a new device.
How to deceive the mass air flow sensor using ECU firmware
The good thing about the previous method is that its implementation does not require complex equipment or painstaking work. If you were able to check the voltage at the output of the flow meter with a multimeter (which means you at least have one), and know how to hold a soldering iron in your hands, installing a resistor in the wire gap will not be difficult. However, the dependence of voltage on air flow mass is nonlinear. And when the throttle valve opens, the error of the signal corrected by the resistor at rest will increase. Accordingly, the fuel-air mixture will not be ideal.
This means that you need to adjust the MAF calibration in the ECU firmware.
Attention! If you do not have experience working with car software, it is better to entrust this operation to professionals.
- We install the specialized tuning program “DFID Corrector” on the laptop.
- We connect the car scanner to the OBD-II connector and establish communication between the ECU and the computer.
Important! During operations with the ECU controller firmware, the 12 volt power supply should not be lost. Therefore, you need to make sure that the battery is fully charged.
After calibration, the data on mass air flow will be correct throughout the entire engine speed range.
Attention: After you install a new flow meter, you must return the calibration to the factory (standard) state.
Why you shouldn’t rush to change a faulty engine air flow sensor
One of the reasons for a decrease in the standard engine power is often a malfunction of the mass air flow sensor located in the intake tract. The AutoVzglyad portal found out how to quickly restore its functionality without going to a car service center.
As you know, the performance of the fuel equipment of a modern automobile internal combustion engine is unthinkable without special sensors.
Their main purpose is to provide electronic feedback between the “brains” of the engine and the functional units of all its systems, of which there are many under the hood.
Such electronic elements also include a mass air flow sensor installed in the intake tract behind the air filter.
By itself, this element almost never breaks mechanically. However, like any part located in the engine compartment, it becomes dirty over time.
And this can already provoke malfunctions in its operation - the sensor begins to make mistakes in assessing the amount of air entering the engine, which leads to a violation of the composition of the combustible mixture.
As a result, the starting of the power unit deteriorates, idle stability disappears, power drops and fuel consumption increases.
A clogged air filter can cause contamination of the mass air flow sensor.
It is curious that both gasoline engines and diesel power units of domestic cars, as well as engines of foreign cars, suffer from similar ailments.
Their sensors also often suffer from the effects of oily dirt and salt solutions that enter the engine compartment, and then, with the flow of intake air, directly onto the surface of the sensor element itself, which generates the control signal.
One of the common reasons leading to accelerated contamination of the air flow sensor is the use of low-quality air filters, which do not perform their task well and quickly become clogged.
In most authorized service centers, when such negative symptoms are detected in the operation of the engine and contamination of the air flow sensor is detected, the technicians do not stand on ceremony and recommend that car owners replace the dirty sensor. The latter is due to the design of this unit, in which replacing the sensor alone is not possible.
The mass air flow sensor is a rather complex electronic unit.
It should be noted that the mass air flow sensor itself is a rather complex, precision-made electronic unit with a dense arrangement of all its constituent elements.
That is why during repairs, if the mass air flow sensor is found to be faulty, it cannot be disassembled, but replaced entirely. However, as service practice shows, making such a replacement is not always justified.
According to experts involved in engine repairs, if the mass air flow sensor does not have mechanical damage, then the expensive procedure for replacing it can be completely avoided. An alternative option in such cases is chemical treatment - thorough cleaning of the sensor using auto chemicals.
Where to buy car accessories
Spare parts and other products for the car are easily available for purchase at auto stores in your city. But there is another method that has recently received significant improvements. You no longer need to wait a long time for a parcel from China: the AliExpress online store now offers the opportunity to ship from transshipment warehouses located in various countries. For example, when ordering, you can specify the “Delivery from the Russian Federation” option.
Follow the links and choose:
How to make a fake MAF sensor
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.
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.
How to trick a broken mass air flow sensor using a resistor
Let's consider the “restoration” option using the example of a VAZ 2110. After an unreasonable increase in fuel consumption, you decide to check the mass flow sensor with a multimeter. The readings at rest significantly exceed the ideal “no higher than 1.02 V” and even the acceptable “1.05 V”.
Accordingly, the engine sees a lean fuel-air mixture and adds more gasoline to the ratio. The result is an increase in consumption without an increase in power.
How to reduce the voltage at the ADC output of a flow meter? We know that based on the calibration of the mass air flow sensor in the electronic engine control unit, each value in volts corresponds to the volume of air in kg/hour.
How to reduce tension? Any novice electrician will tell you that you need to add resistance (additional resistor). Of course, it will not be possible to guess (or even calculate) the required value, so it is better to use a variable resistor in the range from 1 kOhm to 2 kOhm. Old Soviet SP-1 alternators are suitable. They will not fall apart from moisture or temperature under the hood.
Symptoms of malfunction
There are several signs by which you can determine a malfunction of the mass air flow sensor:
- The check engine light comes on on the instrument panel;
- Fuel consumption increases noticeably;
- The car loses dynamics and power, failures occur when trying to increase engine speed;
- Difficulties arise when starting on a hot engine.
But what exactly causes these symptoms? The causes of sensor malfunction are as follows.
- The connector has lost contact.
- The air filter, grilles or sensor temperature detectors are dirty.
- Mechanical damage to sensor elements has occurred.
When the first signs of a malfunction occur, you should definitely check the mass air flow sensor, and then, depending on the situation, clean or replace the device.
Examination
Now let's talk about how to check our sensor. Today, two main methods of checking the mass air flow sensor are used.
- The engine is tested in operation with the mass air flow sensor disconnected. Simply turn off the power from the regulator and start the motor. When the mass air flow sensor is not present during startup, the electronic control unit turns on the power unit in emergency mode. The speed is adjusted to 1500 rpm. After disconnecting the sensor, drive a few kilometers and evaluate the dynamics and power. If the engine is running normally, then the sensor is the cause of the symptoms.
- The second method will require the use of a car tester or voltmeter. After starting the ignition, do not start the engine. The voltage threshold is set on the tester to 2V. The positive probe connects to the yellow wire on the sensor connector, and the black probe connects to the green wire. Next, refer to the table.
Index
Air flow sensor condition
The sensor is functioning normally
Not ideal, but still acceptable voltage readings
Maximum permissible values that indicate imminent sensor failure
The air flow sensor has failed and needs to be replaced
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:
- 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.
- With a sharp release of gas, the speed does not decrease, but remains at around 2-3 thousand for some time.
- 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.
Features, diagnostics and replacement of elements of injection systems on VAZ cars
Below we will look at the main controllers!
Hall
There are several options for how you can check the Hall sensor of a VAZ:
- Use a known working device for diagnostics and install it instead of the standard one. If after replacement the problems in engine operation cease, this indicates a malfunction of the regulator.
- Using a tester, diagnose the controller voltage at its terminals. During normal operation of the device, the voltage should be from 0.4 to 11 volts.
The replacement procedure is performed as follows (the process is described using the example of model 2107):
- First, the switchgear is dismantled and its cover is unscrewed.
- Then the slider is dismantled; to do this, you need to pull it up a little.
- Remove the cover and unscrew the bolt that secures the plug.
- You will also need to unscrew the bolts that secure the controller plate. After this, the screws that secure the vacuum corrector are unscrewed.
- Next, the retaining ring is dismantled and the rod is removed along with the corrector itself.
- To disconnect the wires, you will need to move the clamps apart.
- The support plate is pulled out, after which several bolts are unscrewed and the manufacturer dismantles the controller. A new controller is being installed, assembly is carried out in the reverse order (the author of the video is Andrey Gryaznov).
Speeds
The following symptoms may indicate a failure of this regulator:
- at idle, the speed of the power unit floats, if the driver does not press on the gas, this can lead to an arbitrary shutdown of the engine;
- the speedometer needle readings float, the device may not work as a whole;
- fuel consumption has increased;
- the power of the power unit has decreased.
The controller itself is located on the gearbox. To replace it, you only need to jack up the wheel, disconnect the power wires and remove the regulator.
Fuel level
The VAZ or FLS fuel level sensor is used to indicate the remaining volume of gasoline in the fuel tank. Moreover, the fuel level sensor itself is installed in the same housing with the fuel pump. If it malfunctions, the readings on the dashboard may be inaccurate.
The replacement is done like this (using the example of model 2110):
- The battery is disconnected and the rear seat of the car is removed. Using a Phillips screwdriver, unscrew the bolts that secure the fuel pump hatch and remove the cover.
- After this, all wires leading to it are disconnected from the connector. It is also necessary to disconnect all the pipes that are supplied to the fuel pump.
- Then the nuts securing the clamping ring are unscrewed. If the nuts are rusty, treat them with WD-40 before unscrewing.
- Having done this, unscrew the bolts that directly secure the fuel level sensor itself. The guides are pulled out from the pump casing, and the fasteners need to be bent with a screwdriver.
- At the final stage, the cover is dismantled, after which you will be able to gain access to the FLS. The controller is replaced, the pump and other elements are assembled in the reverse order of removal.
Photo gallery “Changing the FLS with your own hands”
Idle move
If the idle speed sensor on a VAZ fails, this is fraught with the following problems:
- floating speed, in particular, when additional voltage consumers are turned on - optics, heater, audio system, etc.;
- the engine will start to stall;
- when the central gear is activated, the engine may stall;
- in some cases, failure of the IAC can lead to body vibrations;
- the appearance of a Check indicator on the dashboard, but it does not light up in all cases.
Features of the mechanism
Before answering the question whether it is possible to drive without a mass air flow sensor, it is necessary to understand the constituent features of the device. The device is located in the air intake duct, immediately behind the filter. The block from the channel network is responsible for connecting to the control unit. In some modern vehicles, a different connection technology is possible.
It would seem that the operation of the damper is simple. The gas pedal is pressed, opens, the required volume of air is drawn in, the damper closes and a smaller amount is admitted. But in practice things are different.
When driving a vehicle, the driver constantly changes the performance by pressing the gas pedal, therefore the engine does not function equally.
Whirls occur and air cannot enter in the same volume, making calculations difficult.
The mass air flow sensor differs in design. You can ride with anyone as long as it fits the car. Highlight:
- mechanical;
- ultrasonic;
- thermal-anemometric.
The latter are used only on domestic VAZ vehicles. There will be a penalty if you use other components.
The devices are multi-component, but there are no moving parts. This fact explains the stability of operation even in difficult weather conditions and a long service life. It is not possible to repair it; it is easier to purchase a new one. The sensitive element is a nickel mesh or platinum wire.
The characteristics depend on the manufacturing company. A wire that transmits an electric charge is connected to a small structural part. The element heats up above the air temperature, can reach 100 degrees Celsius.
For nickel units the maximum threshold is 75 degrees, and for platinum units - up to 100 degrees.
- scheme;
- frame;
- radiator;
- sensor;
- pipe branch;
- net.
A constant pulse of electricity is required in order to cool the elements affected by the air flow. Direct determination of the air entry rate, that is, its volumetric characteristics, is determined by the degree of how the required current indicators change.
Old-style mechanisms determine this by frequency pulses transmitted to the control panel. Modern equipment models set the required indicators for heating elements and sensors for increasing or decreasing temperature. The element is placed on a special thin film, which is tightly mounted.
Principle of operation
The operating principle is as follows:
- a device is visited at the center of the film that controls heating, its degree and characteristics;
- temperature sensors are connected to the main heating zone, that is, where average indicators are observed;
- two other thermal sensors are located on both sides of the film (one is hidden behind the film, and the second is located directly in the path of the air flow).
When the vehicle is in an inactive state, the sensor will not react in any way, since the temperature of all elements is the same. This is explained by the fact that the incoming flows cool the device, while the performance of the other two remains unchanged - they do not react without driver intervention.
When the movement begins, a rapid passage of air into the equipment is observed, the sensors begin to work. It is from the volume of intake air and the degree of supply of electric current, which is required to compensate for adequate values, that the temperature difference is calculated.
This characteristic determines how much consumable fuel is required and the fuel ratio.
Is it allowed to travel?
You can drive without a mass air flow sensor - yes, but you should carefully assess the situation. When devices fail, the driver does not always have a spare one with him in his emergency kit. Also, sensors for some types of cars are extremely difficult to find, especially when it comes to brands of foreign cars.
In the event of a planned or emergency shutdown of the device, the vehicle operates in emergency mode. Only the throttle valve is responsible for preparing the air-fuel mixture.
The state of affairs cannot be called correct, since it provides ideal performance indicators, quickly breaks down and leads to breakdown of the constitutive parts of the mechanism.
What will happen if you drive without a mass air flow sensor for a long time, it is clear that the car will become unusable.
https://www.youtube.com/watch?v=hUdxKt6hgiE
When operating in emergency mode, only the damper determines fuel consumption. There is high fuel consumption. There will be no fuel savings, which is extremely unprofitable in Russian realities. The crankshaft rotation speed will be at least half a thousand revolutions per minute. There are no gradations.
You can determine whether the sensor needs to be replaced yourself. To do this, the device is turned off and only the throttle valve reads the readings. If, in the absence of equipment, the vehicle moves quickly, then it is faulty and requires replacement.
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.
- We don't need contact No. 1; this is an air temperature sensor.
- Contact No. 2 - 12 volt power supply. If the on-board voltage regulator malfunctions, the air flow sensor may malfunction.
- Contact No. 3 - ground.
- Contact No. 4 - power supply for the mass air flow sensor electronics, an important parameter, the voltage must be stable.
- 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.
Mass air flow sensor design
Position number | Explanation of the position in the figure DMRV VAZ 2114, 2113, 2115 |
1 | Frame |
2 | Connector |
3 | DMRV VAZ 2114, 2113, 2115 |
4 | MAF circuit |
5 | Metal screen |
6 | Air deflector |
7 | Inlet air flow |
ADC codes
ADC code parameters relate to analog sensors of the control system:
- Throttle position sensor
- temperature sensor
- Mass air flow sensor
- Sensor L-probe
- Potentiometer CO.
Physically, ADC codes reflect the voltage that the sensor produces. Typically, these parameters are used to test sensor circuits. If fault codes occur associated with a low or high signal level of such a sensor, then the control system operates in backup modes. In this case, the value of the parameter related to this sensor is selected either from the emergency table or calculated using specified formulas, for example, the coolant temperature with a faulty temperature sensor increases during engine operation.
If, during a physical change in the parameter measured by the sensor, the ADC code remains a constant value, then the electrical circuit connecting the sensor is inoperative.
ADC values are dimensionless, but for the user in scanner testers they are translated into the voltage that a particular sensor produces.
Therefore, using an ADC code, for example, from an L-probe sensor, you can more clearly evaluate the work in the feedback loop system to maintain the stoichiometric composition of the mixture. If the L-probe sensor is inoperative, then the ADC code is in the range of 0.4-0.7V.
The ADC code value (output voltage) from the throttle position sensor can indicate the lower limit at which the system detects sensor error. A throttle position equal to zero corresponds to a voltage from the sensor of 0.52 V.
When the ignition is on, the output voltage from the mass flow sensor (ADC code) should be 1.00V.
The temperature sensor, throttle position sensor, mass flow sensor are powered by a voltage of 5.00V, which is supplied by the control unit. If the control unit produces an unstable voltage, then the sensor readings will change and the behavior of the system in this case is unpredictable.
Optimal operation of a car engine depends on many parameters and devices. To ensure normal operation, VAZ engines are equipped with various sensors designed to perform different functions. What you need to know about diagnosing and replacing controllers and what are the parameters of sensors for VAZ injection engines is presented in the table in this article.
Purpose and explanation of the abbreviation
Flow meters, also known as volume meters or mass air flow meters (not to be confused with mass air flow meters and mass air flow sensors), are installed in diesel or gasoline-powered vehicles. The location of this sensor is not difficult to find, since it controls the air supply, you should look for it in the corresponding system, namely, after the air filter, on the way to the throttle valve (DZ).
Installation location of mass air flow sensor on Gazelle 405
The device is connected to the engine control unit. In cases where the mass air flow sensor is in a faulty condition or is missing, a rough calculation can be made based on the position of the air flow sensor. But with this measurement method it is impossible to ensure high accuracy, which will immediately lead to excessive fuel consumption. This once again indicates the key role of the flow meter in calculating the fuel mass supplied through the injectors.
In addition to information from the mass air flow sensor, the control unit also processes data coming from the following devices: camshaft sensor (camshaft sensor), DD (knock meter), remote sensor, cooling system temperature sensor, acidity meter (lambda probe), etc.
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.