Trouble P0102 - Mass Air Flow Sensor - Input Low

Causes of error P0102

The most common causes of this error are:

• The voltage in the mass air flow sensor circuit is too low (compared to the value specified in the manufacturer's specifications)
• Clogged air filter, resulting in restricted air flow from the filter to the mass air flow sensor
• Placing the electrical wires or the mass flow sensor itself too close to higher voltage components (such as the alternator, ignition wires, etc.) may cause interference affecting the signal sent to the vehicle's ECM
• Contamination or partial clogging of the mass air flow sensor with carbon (this problem can be solved by cleaning the sensor using a special cleaner CRC 05110 mass air flow sensor cleaner - 11 Wt Oz.)
• The mass air flow sensor is not functioning properly, causing the sensor to send incorrect signals to the vehicle's ECM

What does a faulty air flow sensor cause?

Operating an engine with an inoperative/faulty flow meter causes detonation of the fuel mixture in the combustion chamber. This affects the operation of the crank mechanism (crank mechanism) and destroys the piston surface, which can cause a “wedge” in the engine.

What indications should a working mass air flow sensor give?

The voltage of the analog-to-digital converter (ADC) of the flow meter when the engine is not running should be 0.996 V. Indicators of 1.016 and 1.025 V are acceptable, but if they reach more than 1.035 volts, it means that the sensing element of the mass air flow sensor is clogged.

To accurately determine the degree of deviation of the operating flow meter values ​​from normal values, it is necessary to evaluate the engine operation at different speeds.

For example, for an injection 1.5-liter VAZ 2111 engine, if it is in good condition, at idle (860–920 rpm) the correct readings are 9.5–10 kg/hour, and at 2 thousand rpm - 19 –21 kg/hour. If the flow meter at 2 thousand rpm shows about 17–18 kg, then the car will drive stably. If the values ​​are from 22 to 24 kg/hour, then the vehicle will move steadily, but the fuel consumption per 100 km will be approximately 10–11 liters. In addition, the car will have difficulty starting in cold weather due to fuel overflow when the engine warms up.

How does a mechanic diagnose a P0102 code?

• First, the mechanic will connect the OBD-II scanner to the vehicle's diagnostic port and read all the stored data and error codes. He will then clear the error codes from the computer's memory and test drive the vehicle to see if the P0102 again.
• If the error code appears again, a mechanic will visually inspect the air filter, mass air flow sensor, and associated electrical wires and connectors.
• If no problem is found, the mechanic will perform a circuit test using a digital multimeter to check the sampling rate and readings of the sensor to see if the problem is actually the MAF sensor input signal level being too low.

How to check the sensor

Before buying a new MAF sensor, you need to make sure that the old one is faulty. First you need to clean the air flow sensor with a special spray for sensors. Then look at the condition of the air filter. Replace if necessary. In more than half of the cases the malfunction will be fixed.

In order to diagnose the cause of error P0102, you need to do the following:

1. Erase the error code from the ECU.
2. Connect a scanner or on-board computer to the OBD-II connector and make a test drive.
3. If the error comes on again, check all the potential culprits: filter, connector, wiring harness.

In addition, you need to check the electrical circuit using a multitester and measure the voltage between the contacts of the block.

When the ignition is turned off, the connector from the sensor is disconnected. Then the ignition is turned on and the voltage is checked between contacts 2 - 3, 3 - ground, 3 - 4. Between contacts 2 and 3 the voltmeter should show 10 volts, between 3 and 4 - 5 volts, and between 3 and ground there should be no voltage.

After checking, you need to install resistance between pin 5 and ground. In normal condition it will be 4 - 6 kOhm. If the measurement data does not correspond to the nominal value, then there is either a break or a short circuit in the wiring. Resistance diagnostics are performed with the ignition off.

Only after the previous check can a conclusion be made that the MAF sensor is faulty.

Common mistakes when diagnosing code P0102

• The most common mistake when diagnosing a P0102 is to hastily replace the MAF sensor without first checking the associated electrical wires and connector.
• It is also a mistake to neglect to check the mass air flow sensor for excessive carbon buildup before replacing it. Sometimes the problem can be solved by cleaning the sensor using a special cleaner designed for mass air flow sensors.
• Another mistake is neglecting to check the air filter for clogging.

How to replace it yourself

The air flow sensor is located between the air filter and the massive air pipe connected to the intake manifold.

Once you have established that the VAZ error P0102 pops up due to the mass air flow sensor, you can safely go to the store for a new part. A new sensor costs more than 3,000 rubles and is sold complete with the pipe in which it is installed.

Replacement work takes place with the ignition off. First you need to disconnect the block with wires from the sensor. To do this, press the bottom of the chip on the latch and carefully remove the connector. In this case, you need to pull not by the wires, but by the block.

Using a screwdriver, loosen the clamp and remove the rubber pipe from the sensor. After this, two M6 bolts are unscrewed on both sides of the mass air flow sensor.

After removing the part, you need to look at the markings on the body, since the auto industry installs different ECUs on the same models, and it may turn out that a new working sensor will be incompatible with the controller installed on the car.

The sensor is installed in the reverse order of removal. This eliminates error P0102 for Kalina, Priora, Samara - all representatives of the VAZ family with similar injection engines.

How serious is the P0102 code?

• When the P0102 , there are usually no serious problems with the vehicle's drivability. Under certain circumstances, damage or failure of the mass air flow sensor can result in either an increase or an excessive decrease in fuel consumption. If this code is detected, it is recommended that you contact a qualified technician as soon as possible to diagnose and resolve the error.
• You may also have trouble starting the engine, or the engine may run erratically. In some cases, damage to internal engine components may occur.
• Often, if the Check Engine Light comes on immediately after starting the engine, the OBD-II system can be reset and the vehicle will continue to operate normally.

What is the MAF for?

An internal combustion engine runs on a combination of fuel and air. For effective operation, a mixture is required that will burn out almost completely in the cylinders, and for this you need to choose the right ratio.

The mass air flow sensor, otherwise known as the MAF sensor, transmits readings to a computer, which selects the exact proportion of air and gasoline corresponding to certain crankshaft speeds.

What repairs can fix the P0102 code?

To resolve error P0102 you may need to:

• Check for the error code using a scan tool, clear the code from your computer's memory, and test drive the vehicle to see if the P0102 again.

If the error code appears again:

• Reconnecting, Repairing, or Replacing the Mass Air Flow Sensor Electrical Connector
• Repair or replacement of electrical wires related to the mass air flow sensor
• Replacing worn or damaged vacuum hoses and cleaning or replacing a clogged air filter

VAZ fault code P0102 determination of the reasons for its occurrence.

If this fault code is in the memory, do not rush to change the sensor. First you need to check the sensor circuit and the serviceability of the controller. To do this, you need to check the reliability of the connection of the plug to the sensor and the presence of appropriate voltage and connection to ground. To check, it is necessary to disconnect the contact block from the sensor with the ignition off. Turn on the ignition and check for voltage between the contacts using a voltmeter or multimeter in voltmeter mode, 2 -3, 3 - 4 and 3 - ground. To prevent damage to the controller, it is important to use instruments with an internal resistance of at least 10 mOhm for measurements.

If the voltage between contacts 2 -3 is 10V, between contacts 3 - 4 is 5V, and there is no voltage between ground and contact 3, then turn off the ignition and check the resistance between pin 5 and ground, which should be within 4 - 6 kOhm. If the voltage at the terminals does not correspond to the above data, it is necessary to eliminate the break or short to minus or plus of the corresponding wire. If the resistance is close to zero or more than 6 kOhm, it is necessary to eliminate, respectively, a short to ground or a break in wire 4G. If all readings are correct and there is an error, the sensor is faulty and must be replaced. Please note that the sensor is installed in the direction indicated by the arrow on the housing, from the air filter to the intake manifold.

The best inexpensive car scanners

Among the inexpensive models of car scanners, we highlight the following:

• Scan Tool Pro (Black Edition);
• Orion ELM 327 Wi-Fi Micro;
• Launch CReader V+;
• Delphi DS150E.

Next, we will dwell in more detail on the description of each of the presented models, list their features, advantages and disadvantages, as well as the technical characteristics of the devices.

Scan Tool Pro (Black Edition)

One of the best multi-brand car scanners. Provides maximum support for autoblocks and is low cost. Unlike other products, this adapter reads not only the engine state, but also the state features of other systems, including DSC, ABS, ACC, and many others. Connection is simplified as the product supports Wi-Fi and Bluetooth. Extended equipment, clear instructions for use do not require the motorist to have special knowledge in diagnostics.

Price: from 1800 to 1950 rubles.

pros

• reads error codes;
• connection via Bluetooth, Wi-Fi;
• Russian-language programs;
• intuitive instructions;
• ease of connection and use;
• affordable purchase.

Minuses

not found.

auto scanner Scan Tool Pro (Black Edition)

Orion ELM 327 Wi-Fi Micro

The adapter is small in size, compact and at the same time quite functional. It will help you track the condition of your car online at any time. The software has been expanded, performs comprehensive diagnostics, identifies errors and immediately reports them to the owner. The auto scanner is mostly focused on mobility, and is also good at connecting to phones and tablets. In driving mode, it takes on the function of an informant, shows speed, distance, fuel consumption and reports the need to refuel and correct certain problems.

Price: about 1290 rubles.

pros

• small size;
• multifunctionality;
• work while the car is moving;
• connection to mobile devices;
• finding and eliminating errors;
• active work without interruption.

Minuses

• difficult to find on sale;
• the indicators are far from professional equipment.

car scanner Orion ELM 327 Wi-Fi Micro

Launch CReader V+

A stand-alone auto scanner with a screen, there is no need to connect it additionally to a tablet or computer. Data is displayed in several formats - a text string or visual tables and graphs. The level of diagnostics is high-quality, and users do not speak negatively about the functionality. The model works stably and is suitable for different car models.

Price: from 3030 to 3390 rubles.

pros

• autonomy and independence from gadgets;
• advanced functionality;
• presence of a screen on the device;
• high-quality level of diagnostics.

Minuses

There is a screen, but it is small.

auto scanner Launch CReader V+

Delphi DS150E

The scanner is suitable for different car models; its database contains data on many car models (especially if they are equipped with a standard OBD-II connector). All vehicle systems are diagnosed, the device does this quickly and clearly. Some experts do not refuse such a small budget assistant.

Price: from 4900 to 5590 rubles.

pros

• Suitable for more than 100 car brands;
• has a standard connector;
• reads data from on-board devices of the car;
• ease of connection;
• intuitive controls;
• Ideal for garage living conditions.

Minuses

not found.

car scanner Delphi DS150E

Types of on-board computers

There are two types of bortoviks:

• for cars of carburetor type;
• for diesel vehicles;
• for injection type cars.

The first category does not have a wide range of models. In addition, bookmakers of this type have minimal functionality, which makes such a purchase unjustified. If we are talking about the injection type, then for such cars there is the largest selection of BCs.

In addition, on-board aircraft can be divided into several categories:

• Universal multisystems. These sidecars are suitable for any car. For example, the on-board computer on the VAZ 2110 refers specifically to such “station wagons”. In this case, the device is installed on the front glass or on a bracket on the rear.
• Typical (model). Electronic on-board devices (ECUs) manufactured for a specific type of car.

If you decide to sell a car with a model BC, you will not be able to reinstall the useful gadget on a new car, but the station wagon can be safely “relocated”; all you need to do is update the software.

How ABC works

The anti-lock braking system was developed when it became clear that when the wheels suddenly jam, the car loses stability and is difficult to control. Moreover, the quality of braking did not improve, and the car was pretty much carried off the road. Therefore, a system was developed that, by regulating the pressure in the brake system pipes, allows the wheels to turn slightly. This significantly improves vehicle dynamics, allowing the driver to control the vehicle more confidently. But despite its apparent simplicity, this is a rather complex process that requires the coordinated operation of many mechanisms included in the anti-lock braking system. If any of the components fails, a warning lamp lights up on the instrument panel.

You can often hear the question from drivers: “Why is the ABS sensor on?”

It is important to know that when the warning light comes on, it does not necessarily indicate a faulty wheel sensor.

VAZ error 0102 - Low signal level of the mass air flow sensor

Various errors often appear on the on-board computer or during diagnostics with a scanner. Some of them are harmless, while others pose a serious threat to the car. This material tells you how dangerous the common error P0102 is on the VAZ 2114, in what cases it occurs and what to do about it.

Almost all owners of this car have encountered this problem. It is considered one of the most common for this model. But, fortunately, it is not difficult to eliminate the causes of its occurrence.

The VAZ fault code P0102 is not permanent.

If this error code is not permanent, check the reliability of the connection of the block to the sensor, the correct routing of the harness, the presence of insulation damage, as well as the connection of additional consumers to the harness. When inspecting the connection block, pay special attention to possible damage to the contact locks, connections to wires, loosening and oxidation. If necessary, remove the contact from the connector and carefully bend it for a better fit to the mating contact.

When checking the correct installation of the harness, make sure that the harness is not laid near high-voltage wires and the exhaust manifold. In addition, it should not have visible damage. Move the connector and harness with the diagnostic equipment or on-board computer connected and the ignition on. If an error appears during this, it indicates a broken wire or poor contact in the block. If this error appears under heavy load and the throttle valve is opened more than 50%, then the cause is most likely a clogged air filter.

After eliminating the malfunction, it is necessary to erase the fault code from RAM using diagnostic equipment or by disconnecting the battery for 15 - 20 seconds.

Source

What is a knock sensor and why is it needed?

This part is found in cars that use gasoline as fuel. It is intended for injection types of engines. The sensor is located on the engine cylinder block. This is an important part of the control system, the main purpose of which is to control the level of detonation.

There is a similar article on this topic - What is engine chip tuning, pros and cons.

In answering the question of what the knock sensor is responsible for, it should be noted that thanks to it the following vehicle capabilities are realized:

• Fuel economy.
• The ability of the engine to develop maximum power.

Detonation is the electrical impulse created during ignition. It is thanks to detonation that the car starts, complex chemical and physical processes occur inside the engine, and the fuel ignites.

The sensor monitors the vehicle's starting system and regulates its proper operation.

What are the main components of a knock sensor?

The main details of this mechanism are:

• Vibrating plate.
• Piezo type electrical element.
• Signal wire.
• Braid.

Do-it-yourself diagnostics

Various breakdowns of sensors and other devices can cause increased gasoline consumption, incorrect engine operation, and increased wear of car system components. Despite the presence of errors, the VAZ Priora will drive until the driver has to make expensive repairs because of them.

VAZ Priora car

So that the motorist does not suddenly have to face the need for repairs, a special controller is installed on the VAZ Priora, with the help of which the driver can diagnose breakdowns. This can be done either using special additional equipment or an on-board computer installed in the car.

In fact, to carry out diagnostics, the car owner will only need to press a few buttons and count combinations of faults.

For example, you do not have a special tester, so we will look at diagnosing the vehicle for errors using the on-board computer. The BC is built into the dashboard and can be used to read combinations of faults. To do this, you need to activate the auto test mode.

The arrows on the dashboard move to maximum values ​​when performing self-diagnosis of the vehicle

First, turn off the ignition. After this, hold down the daily mileage reset button and turn on the ignition

Please note: the button must be held down. There is an LCD indicator on the vehicle's dashboard, keep an eye on it. When you turn on the ignition, all icons will start to light up, and all arrows (speedometer, tachometer, antifreeze temperature sensor, gasoline level status) will begin to move to the maximum values ​​and back

That is, if all the arrows behave as described here, this means that the sensors and indicators are functioning correctly. Now you need to find the button for switching BC functions - it is located on the right steering column switch. By clicking on it, the software version (1.0 and higher) will be displayed on the screen. Click on this button again. Combinations of faults will begin to appear on the screen. If necessary, you can reset error data here. To do this, press and hold the daily mileage reset button for about three seconds.

The appearance of a fault combination on the LCD screen during self-diagnosis

How does an OBD car scanner work?

I found a rather interesting program Car Scanner ELM OBD2. The utility is free, and with an in-app purchase you can disable advertising, unlock a couple of minor options and thank the developer.

How to set up work via a smartphone: connect the scanner to the OBD2 connector of the car, turn on the ignition, launch the scanner application on the iPhone and connect to it.

You can simply turn the key to the first position to supply power to electrical appliances. However, in this case, some of the scanner’s capabilities, which are related to the operation of mechanisms and assemblies, will be unavailable.

Now you can work with the scanner through the application. After the connection is broken (if you turn off the car or go beyond Bluetooth range), reconnection will occur automatically.

The scanner will act similarly to the Bluetooth module in a car audio system. In some scenarios, you may be able to keep the scanner running while operating your vehicle with it.

The scanner is not only capable of working with errors from the central computer. He knows how to get to the most distant components and assemblies, read their indicators, and notice deviations from the norm.

Here are the five main features of such scanners: