Idle speed sensor VAZ 2114: malfunctions, check, replacement

Many car owners unwittingly became acquainted with the mysteries of the idle speed sensor on their VAZ 2114. The real name of the controller is the idle speed controller (IAC). This is a complex unit in the system of injection engines, which is commanded by electronics (among motorists, “brains”). In case of incidents with IAC, the engine begins to “act up”, causing discomfort and troubles to the driver. Next, we will tell you where the idle speed sensor of the VAZ 2114 is installed, what signs indicate its error, and how to change the IAC yourself.

Device

Modern automakers use 3 types of idle speed sensor: solenoid, rotary and stepper. For VAZ 2114–2115 the latter type is used. IAC is a stepper mini-electric motor that opens/closes the air duct of the intake manifold of the internal combustion engine, thereby regulating the speed (similar to a bolt on a carburetor).

The IAC design has a ring magnet, a lead screw (needle) and 2 windings. When voltage is applied to the magnet and windings, an electromagnetic field appears. As a result, the lead rotor begins to rotate, thereby driving the lead screw through the worm gear. Depending on the position of the rotor, the needle valve is able to control the opening/closing of the air duct of the intake manifold.

For reference. What is a step? This is the distance between the conical shut-off valve (IAC tip) and the intake manifold. It is measured by the number of full rotations of the rotor.

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.

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.
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.

Principle of operation

The balanced relationship of the injection engine components is adjusted by the electronic unit (ECU). When you turn the ignition key on a VAZ 2114, the IAC needle closes the air hole on the manifold. After the engine starts, the ECU calculates the required number of steps and sets the regulator needle to the working position, slightly opening the air channel to lean the mixture.

Taking into account the engine temperature and the position of the needle, the ECU regulates the further operation of the internal combustion engine. On a cooled VAZ-2114 engine, the idle speed sensor will again close the air valve, thereby enriching the mixture and increasing the speed.

For reference! The number of steps is determined by the software (firmware). For example, on a hot engine with a “January 5.1” controller it is usually 110 shg., and on a Bosch - 50 shg. Maximum stroke 250 shg.

Idle speed regulator VAZ 2114 - all its features

IAC - idle speed regulator VAZ 2114, which is also often called a sensor, performs the functions of regulating in automatic mode and stabilizing idle speed.

General information about the regulator

The described idle speed sensor is one of the key components of a car engine, which, together with other devices, ensures the uninterrupted and well-coordinated functioning of the entire “organism” of the vehicle.

The IAC is located on the throttle assembly, or more precisely, on its body.

It is not difficult to find the element we are interested in; it is located near the sensor that controls the throttle valve. Typically, the regulator is connected to the throttle mechanism with small screws. In rare cases, there is also the option of attaching the sensor using varnish.

Idle speed regulator VAZ 2114 - operating principle

The rod located on the IAC, when the driver turns on the car’s ignition, extends to its entire length and then rests against a special calibration hole, which is located in the throttle pipe. After the regulator has marked a certain number of steps, it returns the valve to its initial position.

If the car engine is warmed up, the sensor for the start of adjustment is located at approximately 40 steps. The volume of air constantly changes as the number of steps decreases or increases:

they decrease if the rod is retracted;
they increase as the rod is extended.

The rod stroke on the VAZ 2114 is 250 steps.

A given volume of air enters the internal combustion engine, which makes it possible to qualitatively control the idle. The air entering the engine is studied by the mass air flow sensor (mass flow sensor). And then, based on this analysis, the mass air flow sensor controller directs the required volume of fuel through the fuel injectors. Another sensor, whose task is to adjust the position of the crankshaft, monitors engine speed and controls the functioning of the IAC.

Fault marker and cause

It is very difficult to calculate the breakdown of the IAC. The VAZ on-board computer is primitive and cannot always detect a failure in the system. The owners do diagnostics several times, but there are no errors on the scanner. At the same time, the car works poorly, and the “Check Engine” is stubbornly silent. The owners of the “four” had no choice but to use samples and replace spare parts to determine the cause. Thanks to them, the main symptoms of a malfunction of the idle speed sensor are now known:

poor starting of the internal combustion engine, especially in winter;
floating engine speed when hot, in the range of 850–1100;
the engine freezes if you put the gear in neutral or release the gas;
The firmware reduces the speed to 800–900 on a cold internal combustion engine (less than 40 °C), without waiting for it to fully warm up.

The main reason for DX failure is natural wear and tear. As a rule, wear appears in the lead screw and rotor. Due to backlash, the ECU cannot accurately adjust the needle pitch. Sometimes the winding burns out as a result of a short circuit. But the most common reason is contamination of the cone valve.

Method for checking the sensor using a multimeter

The most reliable and common way to check the functionality of the sensor is to use a multimeter. But to do this, the regulator must first be removed. Typically, it is secured with several screws near the throttle sensor, but on some cars it can be secured with a special solution or varnish.

It is impossible to dismantle the IAC using force, since there is a high risk of damaging the intake system. In such a case, you will have to remove the entire throttle assembly.

To check the electric motor, it is necessary to measure the resistance of the windings. The multimeter contacts must be connected in turn to each of the windings A and B, C and D. If everything works properly, the data obtained will fall in the range of 40–80 Ohms.

As an additional check with a multimeter, the contacts can be swapped. The sensor, in this case, should indicate an open circuit.

Which to choose

If symptoms or diagnostics confirm that the idle air regulator on your VAZ 2114 is defective, then all you have to do is go to the store for a new sensor. Independent auto industry experts and service workshop specialists recommend purchasing an original IAC. Its number is 2112-1148300-02 (sometimes ending: 01, 02, 04). If there is no factory part, then you can replace it with a worthy analogue.

Table 1. Price of idle speed sensor on VAZ 2114

Manufacturer	Number	Amount, rub.
AvtoVAZ	21120114830081	730
KRAFT	KT104900	510
MANOVER	MR21121148	450

Source: autopiter.ru

In addition to the above, the products of the manufacturers “Omega” and “KZTA” have proven themselves well.

How to check IAC

There are a lot of counterfeits on the spare parts market. Popular parts are often counterfeited in poor quality. Even some car owners have complaints about Omega, although the majority of VAZ users praise this manufacturer’s IAC. Sometimes you come across outright dummies. Therefore, service workshop specialists are recommended to organize a check of the idle speed sensor before installation on the VAZ 2114.

Self-diagnosis will require a multimeter, which should be switched to an ohmmeter. The IAC has two windings, and there are four outputs on the block: A, B, C, D. First we test A and B (first winding), then C and D (second winding). For model 2112-1148300-02 the natural resistance is 51 (±2) Ohms, and for 2112-1148300-01 - 53 (±5) Ohms. If the parameters on the multimeter tend to infinity, then there is probably an open circuit in the winding circuit.

Attention! The needle on the new regulator should stick out from the body no more than 23 mm, that is, be in a half-closed position. If it protrudes strongly from the body of the regulator, then during installation the splines of the lead screw can be damaged. Car service specialists will help you return the needle to the lower position.

We check the idle speed sensor on a VAZ-2114 with our own hands: signs of a malfunction

If the idle speed of the car begins to “float”, and its operation as a whole has become unstable, then first of all you should check the idle speed sensor. In this article we will tell you in detail about this, and also tell you how to approach the issue of choosing this sensor.

Video with an overview of the main malfunctions of the idle speed sensor (+ replacement)

Main symptoms of a malfunction

Among all engine problems, “floating” idle speed is especially noticeable, and they manifest themselves in the following:

The engine stalls when changing gears.
The engine speed either rises sharply or drops to a minimum.
The revolutions drop sharply at the moment of stopping with the engine running (at the moment of stopping at a traffic light - approx.).

If such symptoms are present, the idle speed sensor is usually faulty. However, before you start repairing it, you need to understand what it looks like and where it is located.

Sensor location on the engine

The sensor that regulates idle speed on a VAZ-2114 is usually fixed with two bolts next to the throttle assembly. It is easy to recognize by the presence of a power supply and its specific shape.

Idle speed sensor location

Now that we have figured out its location, we can begin diagnostics and, if necessary, repairs.

Troubleshooting

The difficulty in diagnosing the idle speed sensor lies in the fact that its problems will not be shown by the on-board computer, and its functionality can only be checked manually. The same cannot be said about the throttle position sensor, because they have the same symptoms of malfunctions, and the most ordinary on-board computer can identify the latter.

Checking the sensor circuit

Before you start checking the sensor, make sure that the multimeter is working and ready for use.

The idle speed sensor and its “wires” are below the throttle sensor. The throttle sensor is marked with an arrow. The block has been removed from the idle speed sensor.

Please note that on cars equipped with a 1.6-liter engine, it is necessary to remove the throttle assembly mount and move it away from the receiver itself by about a couple of centimeters.

Take a multimeter

Then, on the multimeter, set the “voltmeter” test mode.
We connect the black probe to ground, and fix the red one to the terminals of block A - D.

This is what the pin layout looks like on the IAC power supply block.

If after checking it is determined that the circuit is working properly, then you can proceed directly to the sensor.

Checking the idle speed sensor

When testing the sensor itself, you must connect the sensor to resistance test mode as follows:

The values are normal.

If the test readings were abnormal, you can try to clean it with carburetor cleaner, or purchase a new one.

Which sensor should you choose?

In order to correctly approach the selection of an idle speed sensor for a VAZ-2114, you should know that the last two digits on the sensor article number have a special meaning. Because if the article number of the old one ended with “ 01 04 will be replaced , then there will be no sense in this, because it simply will not work properly.

Native sensor and analogue

Sensors from numbers “ 01 ” to “ 02 ” and “ 03 ” to “ 04 ” are considered interchangeable, respectively.

When choosing this device, also pay attention to counterfeit goods, because there are plenty of them on the modern market.

Replacement

Before you begin replacing the idle air control on a VAZ 2114, you need to prepare. It is better to carry out repairs in a well-lit garage, since on a 1.6 engine (16 valves) you will have to “unfasten” the throttle assembly. On 8-valve engines, craftsmen do without dismantling this mechanism. But sometimes the screws cannot be unscrewed (especially the lower one), so you have to disconnect the fuel supply unit from the manifold, and at the same time clean the dirty channels.

To replace the IAC yourself, you will need a simple set of tools: a durable medium-sized Phillips screwdriver, a 13 mm wrench (head), WD-40 lubricant, aerosol carburetor cleaner and a rag. There is a gasket between the throttle body and the intake manifold. Quite often it is in poor condition due to prolonged use. It’s better to buy a new one in advance (price 30–40 rubles). Step-by-step instructions for replacing the IAC VAZ 2114 (8–16 valves) look like this:

Secure the car with the handbrake.
Remove the negative terminal from the battery.
Remove the engine protective screen (for 1.6).
Loosen the clamps on the crankcase exhaust pipe and the corrugated pipe.
Disconnect the corrugation from the throttle assembly.
Remove the upper idle crankcase ventilation pipe.
Remove the throttle cable.
Unscrew the 2 nuts of the throttle assembly and remove it from the studs.
On the left, below, find the location of the IAC.
Unplug the power plug from the sensor.
Unscrew the 2 screws of the regulator using a Phillips screwdriver.
Clean the assembly from carbon deposits and dirt using carburetor cleaner.
Coat the rubber ring of the regulator with machine oil.
Install the IAC into the throttle mechanism.
Collect everything in reverse chronology.

Attention! Once you have finished replacing the idle speed sensor, do not try to start the car. First you just need to turn on the ignition and wait 10–15 seconds. The system will automatically adjust the IAC to the operating position. Then it is recommended to repeat the operation 3-4 times (masters call this “registration”). Only then can you start the car, warm up the engine and evaluate its performance.

Signs of a malfunction of the idle speed sensor on a VAZ 2114

The VAZ 2114 idle speed sensor is designed to control and develop the required speed on the car engine. Is it really necessary and what is the idle speed sensor responsible for? At its core, it is an electric motor with a cone-shaped needle mounted into the body. Its task is to deliver the necessary (required) volumes of air for the constant operation of the car engine at idle speed.

Its work begins as soon as the ignition on the car is turned on. The conical needle is attached to the rod. The sensor begins to move it, and the needle either opens or closes the calibration hole in the throttle pipe, which stops the flow or, conversely, allows air to pass through. This is the principle of operation of the idle speed sensor. This allows the car to start moving immediately even when the engine is cold. Thus, unstable engine idling of the VAZ 2114 should alert the car owner.

On various websites, forums, and search engines you can come across questions: “What is IAC?” This is an abbreviated name for the idle air speed sensor or control, therefore, in this article we will refer to it differently.

Idle speed regulator VAZ 2114

Troubleshooting

It is not difficult to understand that the problem is in the sensor; for this you do not need to go for expensive diagnostics. There are visible indicators that help determine this breakdown:

The idle speed of the VAZ 2114 floats. This is especially noticeable if you additionally turn on some devices, such as a stove, car radio, light;
When switching to neutral speed, the engine stalls;
The motor is tripping;
Body vibration is also possible. All together, these are already signs of a malfunction of the idle speed sensor. Also an indicator is the lighting of the “Check engine” icon, but in this case it may not always light up.

There are several solutions to this problem:

clean it;
replace the failed spare part with a new one.

But before we decide what will be necessary in this particular case, we first find out whether it can be repaired. In any case, for accurate diagnosis, the regulator must be removed. Below is a picture that, to simplify the search, will show what the idle speed sensor looks like.

Replacing the IAC on a VAZ 2114

We have decided on the appearance, but in order to remove it, we need to decide where the idle speed sensor is located. We focus on the gas pedal, to which the cable goes. We look for the idle speed regulator on the VAZ 2114 opposite this cable, namely on the throttle valve, which is located below its position sensor. It is glued or attached with just two bolts.

To remove it you need:

Be sure to turn off the car’s ignition and remove the battery terminals;
Pull out the connector by disconnecting the wires leading to it;
Unscrew the wires with a suitable screwdriver and remove the spare part itself;
If the sensor is glued, you will first have to pull out the throttle assembly completely, and then carefully peel off the sensor.

Checking status

If you have a tester for checking, the procedure is simplified. But you can diagnose performance without the help of special analyzers. Here you cannot do without the help of a friend, colleague, neighbor or just an acquaintance. You need to connect the connector to the removed sensor. Gently place your finger on the tapered needle and its tip. At the same time, you need to remember that you cannot put pressure on the needle. After this, please start the car (turn on the ignition). The finger should feel slight vibrations (shocks). This indicates the operating condition of the regulator.

Idle speed sensor VAZ 2114

Next, we inspect the IAC itself to identify its contamination. It is necessary to clean it, as this will increase its service life and affect the engine speed and its operation. It is easy to clean. We take a special cleaner designed for the carburetor. It is inexpensive, sold in any auto store, as well as in many hypermarkets in the car department. Dip a cotton swab into the liquid and carefully rinse all contacts.

We also fill the rod, spring and cone needle with cleaner and use an old toothbrush to remove all dirt. To improve performance, we also clean the throttle valve. Before returning the IAC to its place, it is better to also clean the valve and its seat, as well as the entire surface area on which the O-ring is attached. We coat the sealing ring itself with engine oil and put everything back in place in reverse order.

Repair and purchase of a new IAC

Above we looked at the procedure for a working sensor. If during diagnostics you cannot feel the vibration of the needle with your finger, then it is not worth repairing such a unit. It's easier to throw it away and buy a new one. There is no need to worry about this, since the price of an idle speed sensor for a VAZ 2114 is not high. The cheapest are domestic ones. The price tag starts from 350 rubles and depends on the manufacturer and type. There are 4 of them in total. It’s up to you to decide which IAC is best installed on the VAZ 2114, but the ideal option is to replace a new one with a similar one.

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 option 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:

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