Dear customers, in order to avoid errors when sending the connector connecting to the idle air control (IAC), in the "Comment" line indicate which IAC, your car model, year of manufacture, injector or carburetor.

Any breakdown is not the end of the world, but a completely solvable problem. Sensors refer to measuring instruments, they convert the measured physical quantities into electrical signals and display digital data on the display.

The main purpose of the idle air controller (IAC):- changing the crankshaft rotation speed by adjusting the clearance and changing the amount of passing air. It is a component of the engine and is of great importance for the normal operation of the car as a whole.

This air is taken into account mass air flow sensor (MAF) and, in accordance with its quantity, the controller supplies fuel to the engine through the fuel injectors. By position sensor crankshaft(DPKV) controller monitors the number of engine revolutions and, in accordance with the engine operating mode, controls the IAC, thus adding or reducing the air supply bypassing the closed throttle valve. On warmed up operating temperature engine controller Electronic engine control unit JANUARY 7.2 (81 contacts) for VAZ 2110-2112 Art. 21114-1411020-31 maintains idle speed. If the engine is not warmed up, the controller increases the speed due to the IAC and, thus, ensures the engine warms up at increased crankshaft speeds. This mode engine operation allows you to start driving the car immediately and without warming up the engine.

Connecting block 2112 – 1148300АХ (4 contacts assembled with wires), is one of the elements of the controller harness, connects to the IAC with electronic system fuel injection on VAZ 2108, 2109, 21099, 2110, 2111 cars; 2113; 2114, 2115; 2112, VAZ 2170, VAZ 2190, Kalina 2, VAZ-2121, VAZ 21213-21214i, VAZ-2123, VAZ-2131, Largus and their modifications. The block can be used for self-made cable. The contacts are already crimped onto the wires (wire length 100 mm) and inserted into the connector, you can install them on the car.

The idle speed sensor (IAC) consists of a stepper motor, a spring and a rod ending in a conical needle. Using two threaded screws, the VAZ idle speed control is attached to the body throttle assembly. When the car owner turns the key in the ignition, the rod extends, resting against the mounting hole: the sensor reads the steps and the valve returns to its original position.

Replacement of contact carrier 21203–1148300АХ (4 contacts) assembled with wires, which is an element of the ignition system harness, connecting the idle air control on VAZ 2108, 2109, 21099, 2110, 2111 vehicles; 2113; 2114, 2115; 2112, Kalina, VAZ 2170, VAZ 2190, Kalina 2, VAZ-2121, VAZ 21213-21214i, VAZ-2123, VAZ-2131, Largus, VAZ 2120 and their modifications with an electronic fuel injection system, can be done independently, without contacting specialized maintenance services.

Other article numbers of the product and its analogues in catalogues: 212031148300АХ, 211201148300АХ

VAZ 2108, 2109, 21099, 2110, 2111; 2113; 2114, 2115; 2112, Lada Kalina, VAZ 2170, VAZ 2190, Kalina 2, VAZ-2121, VAZ 21213-21214i, VAZ-2123, VAZ-2131, Largus, VAZ - 2120.

Any breakdown is not the end of the world, but a completely solvable problem!

How to identify a problem with the idle air regulator (IAC) on a VAZ car of their modification?

How to replace the idle air regulator (IAC) yourself at Chevrolet car Niva -2123, VAZ 2131 (NIVA) and VAZ - 2120 “Nadezhda” their modifications?

How to independently replace the connector on the ignition system harness to connect the idle air control (IAC) on a VAZ car of their modifications?

With an online store AvtoAzbuka repair costs will be minimal.

Just COMPARE and BE SURE!!!

In a simplified form, the idle air control allows the engine to operate when starting and subsequently stopping the car, for example, at intersections. It supplies the missing amount of air to the fuel mixture of the injector for normal operation of a cold engine or when stopping the car without stopping the engine.

Purpose of the IAC regulator

The idle air regulator is used exclusively in electronic ignition systems:

• proportions fuel mixture in the injector there is an on-board computer;
• the amount of gasoline or diesel fuel for each cylinder is measured by the ECU;
• The electronic ignition is equipped with sensors DPKV (crankshaft), TPS (throttle valve), MAF (air), DD (detonation), the signals of which trigger fuel pump and the ignition is distributed to specific cylinders;
• when the gas pedal is released, the fuel damper is completely closed, the proportions of the fuel mixture are violated, combustion products are sucked back into the combustion chamber due to the difference in pressure in the intake and exhaust manifold.

Based on the results of the air sensor signals, the controller makes a decision to further enrich the fuel mixture with air, ignoring the readings of the throttle sensor at this moment.

The chip on the IAC transmits a signal from the ECU; a bypass channel opens in the idle air regulator, through which air passes in the injector or additional fuel in the diesel engine. Engine speed is leveled, piston and crankshaft wear is reduced.

Operating principle

IN carburetor engines the problem of enriching the mixture when starting the internal combustion engine The solution was the starting handle and shims. With the emergence electronic ignition This is done by the idle air regulator in conjunction with other sensors and the ECU. Its operating principle is as follows:

• IAC calibration is performed by the ECU controller automatically after detecting this sensor in the system;
• in fact, the IAC is a stepper motor with a conical needle in a special hole in the throttle valve bypass channel;
• The IAC contact does not transmit any signals to the “brain” of the machine, but receives them from the controller, therefore it is not a sensor, but actuator– electrovalve;
• in turn, the on-board computer “sees” that there is not enough air in the fuel mixture based on the signals from the mass air flow sensor, compared with the signals from the air flow sensor;
• Voltage is applied to the XX regulator, the needle leaves the channel, and the missing amount of air enters the mixture for mixing.

In addition, the ECU receives signals about the temperature of the coolant and oil in the system. When starting in the cold season, it is necessary to warm up the engine to operating temperature in order to reduce wear on friction parts, so the IAC channel opens slightly to enrich the mixture for the injector, even without the driver pressing the gas pedal.

At the moment of start, the operating algorithm is as follows:

• the key turns, the ignition turns on;
• the rod extends all the way, the needle blocks the bypass channel;
• at the moment the rod rests against the calibration hole, the computer counts the steps backward;
• voltage is applied to the windings, the valve returns to the open position.

The number of reverse steps is programmed in the device firmware. For example, for Basch modifications on a warm internal combustion engine it is 50 steps, January – 120 steps, respectively. In total, the stroke of the rod is divided into 250 steps; the further it extends from the windings of the stepper motor, the greater the number of steps the ECU will count. When purchasing a new IAC, the distance from the mounting flange to the rod needle should be exactly 23 mm.

Injector

For work injection engine Pure gasoline is not suitable, so a throttle valve with an individual sensor of its position at each moment of time is installed at the inlet of the manifold. When starting the engine or stopping the machine with the engine running, the following occurs:

1. the computer receives information about the engine shaft speed;
2. analyzes how the motor works, that is, clarifies the intended purpose;
3. then the readings of the throttle position sensor and the air are compared, that is, the controller “understands” that the damper is closed and a lean mixture enters the cylinders;
4. The IAC valve opens, air is supplied bypassing the damper to maintain the speed at the programmed level

In fact, several electronic ignition system devices are involved in the process. If the car stalls or there are symptoms of other malfunctions, diagnostics are performed manually, since feedback(self-diagnosis) this device does not have.

IN diesel engine There is no throttle valve, the idle speed control is useless, other methods are used to regulate low speeds.

Design features

At the stage of the emergence of DHC, solenoid and rotary idle speed sensors were used. They had two positions, similar to a valve - Open/Closed, which reduced the efficiency of engine speed adjustments. Currently, they have been replaced by a 4-step valve with stepwise bypass supply adjustments.

If you disassemble the IAC, you can see that it is assembled from four parts:

• stepper motor;
• four-position rod;
• spring;
• needle.

When voltage is applied to one of the four windings, the coil is magnetized, interacts with the magnetic ring, and moves the rod to one of four positions. Accordingly, the number of breakdowns of this electrical appliance is as limited as possible:

• the bypass channel is clogged;
• windings burn out;
• the needle or spring breaks.

The sensor is positioned by manufacturers as a “consumable item,” that is, it is considered conditionally unrepairable. It is cheaper to replace the whole thing than to disassemble and repair individual parts. If they are not on sale, you need to grind them yourself.

However, the first reason can be eliminated on our own– with the connector disconnected, remove the regulator to clean the bypass channel with universal WD-40 spray.

Installation location

Knowing the principle of operation of the IAC, it is very simple to determine where the valve is located - near the throttle valve and its spatial position sensor TPS.

It is extremely rare that the sensor is glued to the damper body with varnish; in other cases, the device is fixed with two screws, for which there are mounting holes. The main task of how to adjust the IAC valve with your own hands when installing it is to ensure a distance of 23 mm from the needle to the landing flange.

Before removing the regulator for replacement, you should study the markings. IACs marked 01/03 or 02/04 are considered interchangeable. If you put 02 instead of 01 or 03, the device will not work correctly.

The idle air control control receives a single harness of four wires from the ECU. Below is a diagram of the distribution of the electric motor windings.

The main problem is diagnosing the sensor on your own. Simply applying voltage to its terminals to check functionality will not work, since the ECU does this pulsed. Windings burn very rarely, more often they occur mechanical problems, for example, a bent rod or a clogged bypass channel

At a service station, the sensor is checked on stands capable of reproducing an ECU pulse. Even with a multimeter, a car enthusiast can only verify the integrity of the windings and the absence of a short circuit between them, nothing more.

Signs of failure

The main symptoms that the idle speed sensor is not working correctly are:

• speed in parking mode is unstable;
• reduction in crankshaft rotation speed when any consumer is turned on (windshield wipers, headlights, air conditioning, radio, heater);
• no increase in shaft rotation speed when starting the internal combustion engine;
• stopping the engine when turning off a gear or changing gears.

Attention: These symptoms are not 100% the cause of IAC failure, as they are similar to sensor failure TPS dampers. However, in the latter version it lights up Check error, and the idle speed controller with control system the engine is not connected, does not have self-diagnosis.

Diagnosis of IAC

Ideally, diagnostics of the regulator should be carried out on a stand that can reproduce the pulses of the on-board computer. In practice it is expensive, they are used budget ways checks. In any case, the algorithm of actions at the initial stage is the same:

1. drags on hand brake, anti-recoil devices - shoes - are installed under the wheels;
2. disconnect the “-” terminal from the battery;
3. knowing where they are TPS sensors and mass air flow sensor, the location of the IAC is determined;
4. the valve is disconnected from the on-board computer (the plug is pulled out of the connector).

Further steps differ for different verification methods.

Manual check

The simplest method for checking IAC in an electronic intake distribution system is manual diagnostics (an assistant will be required):

1. the IAC plug is disconnected from the connector;
2. two screws are unscrewed and the device is dismantled;
3. the regulator is reconnected to the ECU, but remains in the hands of the master;
4. The assistant starts the engine, at this time the rod should be completely retracted into the coils, then, having received an impulse from the computer, extend a certain distance.

In other words, the functionality of the stem is checked, the owner makes sure that this part is not bent or jammed inside the valve. However, this does not provide a 100% guarantee that this modification IAC is fully consistent with the controller ECU firmware. The needle extends, but by an unknown amount. In the first case, the connector is checked, in the second - the plug; the markings are only on the plug.

In the classic version of checking “from simple to complex,” this stage is the initial stage; then you should check the integrity of the wires and coils, the condition of the bypass channel, and needle wear. Only after these steps can you assemble a homemade stand with a pulsed voltage supply for complex diagnostics RXX.

Diagnostics with a multimeter

At this stage, you will need an IAC tester, which is checked with this device in two modes:

• ohmmeter - when connecting contacts C – D and A – B with the multimeter probes, the resistance should have a value of 40 – 80 Ohms, D – C and A – D should be equal to infinity;
• with a voltmeter - when the ignition is turned on, the voltage reaches 12 - 20 V.

Attention: IAC adjustment is performed automatically on-board computer after each connection of the device plug to the socket. After dismantling, it is recommended to lubricate the bypass channel with WD-40 spray to clean it. This measure is preventive, even in the absence of contamination of the bypass channel, in the gap of which the regulator is located.

Pulse testing on a homemade stand

Since the stand costs 1,500 - 1,800 rubles, and the regulator 300 - 500 rubles, purchasing the device is not economically profitable for the average user. Simple scheme without microchips is shown below:

• it uses 6 V charging from any mobile device;
• plug blocks are commercially available;
• First you need to disconnect the IAC from the on-board controller, then check the stroke of the rod;
• a bright glow of the lamp in the diagram indicates a malfunction of the rod itself;
• If the lamp burns at the incandescent level, the unit is considered to be in good condition.

Using a cleaning agent will restore the functionality of the rod, but only if it is clogged. If this part is bent, the entire regulator will need to be replaced.

Basic faults

The above symptoms of malfunction usually occur in the following cases:

• the bypass channel of the throttle valve is clogged with dirt;
• the integrity of the wires or coils is damaged;
• The ECU firmware does not match the IAC modification.

Checking using the above methods reveals all the causes of the problem. Whenever disassembling the regulator or throttle assembly, it is recommended to clean the IAC with special liquids/sprays.

Cleaning the needle and bypass channel

To provide access to valve parts, removal of the IAC is required using the following technology:

1. disconnecting the block from the connector;
2. cleaning the connector contacts and plug with a cotton swab soaked in WD-40;
3. unscrewing screws with a curved screwdriver;
4. removing the regulator to check the condition.

Attention: There is no need to disassemble the regulator, just spray the spring and rod with needle with WD-40 spray, wait for it to dry, and at the same time clean the throttle bypass channel.

Adjustment is made by the controller itself on-board network. However for stable operation engine, check the distance from the mounting flange to the protruding needle cone. By default it should be 23 mm.

Nuances of choosing an idle speed sensor

The original idle speed sensor is marked as XX-XXXXXXXX-XX. The last two digits indicate the compatibility label:

• odd (01 and 03) are interchangeable, even (02 and 04) are also interchangeable;
• These groups are not interchangeable with each other, that is, instead of the “native” 02, valve 01 or 03 cannot be used.

Even with original regulators, it wouldn’t hurt to additionally lubricate the IAC with a mixture of lithol and WD-40 (spring and rod). Since replacing IACs with your own hands is in demand among car enthusiasts, there are counterfeit regulators that can be identified by the following characteristics:

• there are no distinctive marks on the packaging;
• sticker yellow color on a body without frame;
• dark needle tip;
• thin black sealing ring instead of a thick red seal;
• body rivets do not have heads with a diameter of 3 mm;
• a white spring instead of a black product with frequent winding;
• the body is 1 mm shorter.

to make life easier, which, with certain skills,
easy to do at home

TESTER FOR CHECKING NOZZLES
© Tom, Miha

Specification: C1 -15 pF, C2 -8 -30 pF, C3 -0.1 µF, C4 -0.047 µF, C5 -470 -25 V, C6 -0.1 µF, C7 -2200 x25 V, R1 -4 .7 –6 .8 MOhm, R2 -130 kOhm, R3 -100 kOhm, R4 -10 kOhm, R5 -10 kOhm, R6 -1 MOhm, R7 -1 .2 kOhm, R8 -130 Ohm, R9 -220 Ohm, R10 -0.2 -0.25 Ohm, R11 -470 Ohm L1 -200 µH, Z1 -400 kHz (50 -800 kHz)

DD 1,DD2 -K561 IE16, DD3 -K561 TM2, DD4 -K561 LE5, VD2 -KD212, VD1 -KD521, VD3 -KD213, VT1 -KT3117, VT2 -KT817, VT3 -KT3102

YA 1 -Nozzle
S.A. 1 - Select pulse duration
S.A. 2 - Select the number of pulses
S.A. 3 -Enable continuous mode
S.B. 1 - “Start”

Short description : DD 4 .1 – master oscillator, quartz is used for stability. The DD1 counter contains a generator for the duration of the injector unlocking pulses. The pulse duration can be selected from 2.5 or 5 ms using switch SA1. The DD2 counter has a pulse number dispenser. The number of pulses is selected by switch SA2. Switch SA3 (fixed) can be used to enable continuous mode. This is necessary when washing injectors, including with ultrasound. SB1 – “Start” button; when you press it, the dispenser starts working. C3,R3 – used to set DD2,DD3.1 to zero when turning on the power. VD1, R6, R5, C4 – suppresses SB1 bounce. You can do without it, but if you press SB1 for a long time, the dispenser may turn on again. VT3 is a parody of short circuit protection; with it, VT2 (KT817) can withstand a couple of cycles of dispenser operation. Instead of VT1, VT2, you can put a composite KT972 or KT829, but then we lose another 1 volt on Unas.ke. When powering the device from battery Car power stabilization chips are not needed. If from another source, then in series with L1 you need to put a resistor and a zener diode of 10–15 V. Figure 1 shows the signal at the output DD4.4. The duty cycle is close to the operating conditions of the signal at the injectors. Races can only be recorded with a good oscilloscope and they do not affect the operation of the device. The division coefficients of the counters can be changed as needed - these counters allow this to be done within wide limits, but in multiples of two.

INJECTOR TESTER FOR KR1006 VI1
© UKR-VLAD

Another option sent by Vladimir, aka UKR-VLAD, from abroad, from Ukraine.
D1,D2 -KR1006 VI1. D1 - burst duration FORMER (adjustable by R1) D2 - pulse duration on the injector (approximately 5 ms. adjustable by R2). P1 - I made it from 4 MP (convenient - you can set any combination)

To start you need:
1. Connect the injector connector to the tester
2.Apply power to the tester
3.Select an injector number or several
4. Press and release the button (no more than 1 second)

The tester is made to a minimum. but it does everything necessary and is quite stable.

Simulation device DPKV signals
© Mikhail Ukhanov. Rostov

Brief description of the scheme: A generator with a variable frequency is assembled on elements D1 .1 ‚D1 .2, since the output from the generator has an asymmetric meander, then there is element D2 .1 which divides the frequency by 2 and generates the correct signal. The signal is sent to counter D3, the counter has a dialed division factor of 60, the output pulse from the counter goes to the trigger latch D2.2 and resets its output, which disables counting on element D1.3. Since the duration of the pulse at the counter output is one clock cycle, we have a reset trigger output for two clock cycles. And at the next positive edge we set the trigger output to one, thereby allowing counting at output D1.3. Next, the signal enters the transistor, and a non-polar signal is generated with a count of 58 pulses 2 passes.

The scheme was tested on JANUARY 5 .1 .1 . The number of revolutions simulated by the circuit is from 240 to 10200 rpm. At the same time, there are no errors on the crankshaft sensor.
Recommendations: it is advisable to use a logarithmic frequency control resistor; the K564 IE15 counter can be replaced with two K561 IE8 counters by slightly adjusting the circuit.

MZ tester program for Bosch systems M1.5.4
© Mobil (Yuri)

The program is designed for testing ignition modules. The program is sewn into ROM, the ROM is installed in the ECU in place of the standard one for the duration of testing. On high voltage wires grounded arresters are installed. Remember to be careful when working with high voltage! After turning on the ignition, the CE light begins to flash, when you press the gas pedal, the ECU begins to generate control signals to the ignition module with a duration of 2.8 mS, a spark should appear at the spark gaps. The frequency of sparking depends on the degree to which the gas pedal is pressed; the harder the pedal is pressed, the higher the frequency. During sparking, the CE light is constantly on.

The spark formation frequency translated into engine speed can be approximately estimated using the tachometer. If you release the gas pedal, the formation of control signals on the MH will stop, and the CE light will begin to blink. This program allows you to evaluate the performance of the ignition module without removing it from the car, also testing
directly on the car allows you to check high-voltage wires, wiring to the MH and ECU outputs that generate control signals.

The program was written and tested on a BOSCH M1 .5 .4 2111 8 V 1411020 ECU, but as far as I understand, it will also work on block 70. I would like the program to be tested on 40 and 60 blocks. Impressions, suggestions and comments are accepted at [email protected] or in a conference. Download program .

The program can be sewn not only into 27 C512, but also into 27 C64, 27 C128 and 27 C256, after programming it is necessary to bend legs 1 and 27 (so that they are not inserted into the panel) and connect them with leg 28 for 27 C64, 27 C128, for 27 C256 you need to bend 1 leg and
connect it with 28.

Tester for checking the speed sensor (DS) circuit
© Oleg Bratkov

One way to check the serviceability of the speed sensor and its electrical circuits– use a speed sensor emulator. You can, of course, connect another, control DS, and by turning its shaft, ask an assistant or driver to watch the arrow on the instrument panel - does it twitch? Well, there are still options...

The emulator is a generator on the “555” timer, a domestic analogue of the K1006 VI1. There are many different schemes for quickly retrieving odometer readings, and almost all of them can be adapted for this. However, the output of a real DS is an “open collector”, therefore, for proper matching with the DS circuits, a low or medium power transistor, almost any one, is used. It is advisable to use power protection, a 10...50 Ohm resistor and a diode in series, and then a protective diode or varistor. Instead of a transistor, it is also advisable to install a modern electronic key.

Good protection will provide long life devices. The generation frequency is determined by the capacitor C*, resistors R* and a 2 kOhm resistor connected between pin 7 and the power wire, and should be 166.666 (6) Hertz for 100 km/h, or with a pulse repetition period of 6 milliseconds. For greater stability, capacitor C* should not be ceramic or electrolytic. It is better to use capacitors of the K73 series. In a particular case, such a frequency was obtained with the ratings of the radio components indicated on the diagram and C*=1 μF, R*=2.7 kOhm. It is necessary to take into account the spread of parameters of radio components :) Put trim resistor, set the frequency and replace it with a constant one. With a smaller capacitance C* and a smaller resistance R*, the frequency is higher. Then coat it with varnish and fill it with “chemical metal” or resin, in one piece with the connector. You will get a trick for checking the DS :)

Well, the check itself: Complaints about the speedometer not working, an error in the ECU “speed sensor is faulty.” We remove the connector from the DS and plug in the emulator. The LED on the emulator lights up - there is power. The speedometer needle has deviated, the ECU (via the diagnostic line) shows the known speed. It’s not necessarily 100 km/h, but how much will be achieved during the manufacture of the device. Conclusion - either the DS itself or its drive is faulty.

IAC check

The IAC has two electromagnetic windings that are not interconnected. One winding moves the needle forward, the other winding moves it backward. The needle moves one step at the moment power is supplied to the winding, the next step of movement is the supply of power in reverse polarity to the same winding.

Pressing and releasing button S2 causes the needle to move; the position of switch S1 sets the direction of movement. I suspect that the IAC mechanism uses the anchor principle. © Oleg Kravchuk aka Ol-102 iL

Another, more advanced and advanced tester was proposed by E. Gorbatko (aka mster2002, [email protected]). This small freeware program allows you to control the Idle Air Controller, changing the speed and direction of movement, by connecting it through a small circuit (the connection diagram is attached, you will need a microcircuit, which can be obtained from the GM VAZ unit) to the LPT port of any personal computer computer.

And finally, the IAC tester from ALMI

The tester is designed to check the serviceability of the idle speed controller with a stepper motor (hereinafter referred to as IAC), installed on VAZ vehicles.

Logic of operation:

1 . When the power is turned on, the IAC is initialized; for this, 255 steps are performed in the direction of retracting the rod, then 70 steps in the direction of extending. This logic is reverse to normal IAC work as part of the throttle pipe, since extension of the rod by 255 steps is unacceptable if the IAC is removed from the DP (the rod can disengage and jump out along with the spring).
2. After initialization, the device is ready for use. Pressing the “extend the rod” and “retract the rod” buttons leads to the corresponding actions. When extending the rod, be careful, it may disengage and jump out along with the spring!
3. Continuous test. If you press both buttons at the same time and hold them for more than 3 seconds, the device will begin periodically retracting and extending the rod by 255 steps. To stop the test, press any button.
4 . Using a potentiometer, it is possible to adjust the speed of movement of the IAC rod.

Explanations for the diagram:

1 . The LM7805 5 volt stabilizer can be replaced with any other one, including one in a TO-92 (78 L05) package, since the current consumed by the microcontroller is very small.
2. It is better to use a film type capacitor in the circuit of the 1st leg of ATTINY12, since ceramic capacitors of such capacity have a significant TKE (capacitance strongly depends on temperature).
3. The IAC driver can be used TLE4728 G or TLE 4729 G. Depending on the type of driver, use the appropriate type of control program! The TLE4728 G driver can be taken from a faulty Bosch MP7 .0 ECU, the TLE4729 G driver can be taken from a January‑5 ECU.
4 . The ATTINY12 L microcontroller must be programmed (flashed) before installation in the circuit.

Firmware and description inside the archive.DOWNLOAD

Acoustic tester TPS

To check the TPS, the simplest device from Sergey Uvarov (aka ZERG) for express checking the sensor “by ear”. Simple, but very efficient device, operating on the “old rustling radio” principle. Diagram and description.

FITTING for a pressure gauge, for checking the fuel pressure in the rail.

Due to numerous requests, we include a drawing of a fitting for connecting a pressure gauge to the ramp. Drawing made and kindly provided by Hass & Dodgev. For sealing, use any suitable rubber tube with an outer diameter of 8 and a length of 6 mm. The drawing that you need to print and take to the turner. If a turner suddenly starts telling you that such threads don’t exist, feel free to turn around and go to another turner. In the end, there will be a specialist who will make a fitting for you.

Connector diagnostic equipment for VAZ cars.

To connect diagnostic equipment to the block, you can use a pin contact of the appropriate diameter, but it is much more convenient to make a specialized connector. This design was developed by NPP NTS to connect its diagnostic equipment. In a slightly modified form, these connectors can be found at car markets in Tolyatti.

Disassembling the 55-pin ECU connector.

First you need to look at the photo on the left - the design of the terminal, and it is intricate, reinforced on both sides with sufficiently elastic flat springs, so that simply pulling out the wire or picking up one of the springs is useless, any attempt to compress one of them (for example, with an awl) leads to that the other spring is even more firmly fixed in the seat.

To facilitate disassembly and extraction of terminals with wires, the connector must be disassembled, i.e. not only remove the protective casing, but also separate the upper halves from the lower. In this case, the side holders on which the terminal numbers are written may break off. Nothing wrong with that. At the end of the procedure, both halves of the connector and the side holders are firmly glued together with ordinary Japanese-Chinese super glue (for 2–3 rubles). Then look at the photo of the finished tongs; you can see that their design is primitive. The purpose of these pliers is to compress both springs together in the socket. Therefore, their dimensions are adjusted to the connector socket.

This “miracle of nature” is made from available materials. I came across a steel wire with a diameter of 3 mm. An ordinary nail will do. We cut the wire into three pieces 2.5 cm long and twist it with something, or solder it, or weld it, or glue it, etc. In general, we connect firmly. The photo shows a twisted version copper wire and soldered using phosphoric acid. Next stage: sharpening. You will need a flat file and a vice to adjust the dimensions. Finally, we insert the pliers into the connector, press with a little force, click and... after 3–5 minutes you have 20–30 wires with terminals in your hands. Pull out all the wires. They are then inserted into the glued connector very easily.

January 14, 2018

In cars equipped with an injector, for idle speed engine and cold start individual answers actuating mechanism(РХХ), controlled by the controller. Although its design is simple and reliable, during the operation of the car the element may not work correctly or, like any other part, fail for a reason normal wear and tear. How to identify the symptoms of a malfunction and check the idle air control in garage conditions, is described in detail in this publication.

How does the regulator work?

In everyday life, the IAC is often called a sensor, although in reality it is not one. The element is a stepper motor housed inside a non-separable housing. Only the spring-loaded rod with a cone-shaped tip protrudes outward. At the command of the ECU, the engine extends or retracts the rod to a certain distance.

The idle speed sensor is located in the throttle valve block, the working cone is extended into a small cross-section bypass channel. Since the engine starts and idles without pressing the accelerator pedal, the mentioned channel supplies air to the cylinders when the throttle is closed. The task of the IAC is to regulate the amount of air flow, blocking part of the flow area with a cone.

To better understand the issue, it is worth presenting the operating principle of the idle speed sensor in the form of an algorithm:

1. After the driver turns on the ignition, the controller activates the governor motor, forcing the idle air passage to open. The ECU calculates the opening amount using a temperature sensor - if the engine is cold, the rod will move back more.
2. At the moment of startup, the injectors supply an enriched mixture to the cylinders. Then the amount of fuel is reduced so that the engine does not “suffocate” and stall. The speed is monitored by the control unit using a crankshaft position sensor.
3. The volume of air entering through the IAC is taken into account by the mass air flow sensor located on the inlet pipe, while increased crankshaft speeds are maintained (1200–1500 rpm).
4. By temperature sensor the control unit “sees” that the engine is warming up and gradually reduces idle speed, giving the command to the IAC to cover the cross-section of the bypass channel. When the temperature reaches an acceptable value (60 °C or more), the regulator maintains the speed at 850 rpm.

Note. If a warm engine is started, the controller immediately sets IAC rod to the operating position corresponding to normal idle speed.

Symptoms and causes of IAC malfunction

Signs of a malfunctioning idle speed sensor appear as follows:

• during a cold start, the crankshaft speed does not increase, which is why the engine runs unstable and tends to stall;
• there is a drop in the number of idle revolutions after a significant increase in the load on the generator - turning on headlights, electric heaters, and so on;
• The engine periodically stalls when a gear is switched off manual transmission(the symptom manifests itself during movement);
• The speed “floats” - it spontaneously increases and decreases.

Important point! There is a misconception that a regulator failure is necessarily accompanied by the indicator turning on Check Engine on dashboard. Since the element is an actuator, the light warning option is not provided in all cars.

If the car shows signs of IAC malfunctions in the form of floating engine speeds at Idling, advanced diagnostics may be needed. A spontaneous change in the crankshaft rotation speed occurs for many reasons - failure of a sensor, air leaks, gas distribution malfunctions, and so on. It is better to start troubleshooting by checking the regulator.

IAC failure occurs for three main reasons:

1. Break or bad contact in the power circuit. Simply put, there are problems with the wiring.
2. Breaking stepper motor due to normal wear and tear. IN in this case Only replacing the idle speed sensor will help.
3. Contamination of the rod and cone with oil deposits.

There is a fourth reason - problems electronic unit management. The problem is quite rare and is accompanied by additional signs– increased gasoline consumption, unstable work in all modes, difficult starting and the like.

Oil deposits get onto the rod thanks to secondary gases sent by the crankcase ventilation system for re-combustion. How more worn out engine, the more deposits accumulate on the working cone. As a result, moving the rod becomes difficult; in advanced cases, the mechanism simply jams.

Sensor diagnostic methods

The easiest way to check that the idle speed sensor is working is to start the engine and remove the power connector from the block. When the element is in good condition, the speed will drop sharply and the engine will stop - when the power supply is turned off, the spring will push the cone forward and the cross-section of the bypass channel will completely close. If the engine operation remains the same or changes slightly, move on to other testing methods.

The next stage of diagnostics is measuring the supply voltage, performed in this order:

1. Disconnect the IAC connector and turn on the ignition.
2. Using a voltmeter, measure the voltage at the corresponding contacts of the removed connector (in VAZ cars these are terminals marked A and D).
3. If there is no voltage or does not reach 12 volts, you need to look for a problem in the electrical wiring. Otherwise, proceed to diagnosing the regulator itself.

In VAZ cars, you can check the performance of the stepper electric motor without removing it from the car. Using a multimeter, measure the resistance between the following pairs of contacts: A - B, C - D (it should be 53 Ohms). Then measure other pairs - A - C, B - D, on a working regulator the device will show infinity.

Further checking of the idle speed sensor is carried out as follows:

1. Disconnect the power supply, unscrew the fastening screws and remove the element from the throttle body.
2. To prevent contamination of the rod, clean the cone and spring with a soft-bristled brush, using kerosene, diesel fuel, or better yet, carburetor cleaning fluid. Do not use acetone or solvents like 646 - they will destroy the plastic.
3. Blow through the cleaned part and connect the connector.
4. Place your finger on the rod and ask an assistant to turn on the ignition. The cone of a functioning regulator should move noticeably. If nothing happens, feel free to change the sensor.

Advice. If a strong oil deposit is detected on the working part of the IAC, it is highly advisable to perform the procedure for cleaning the throttle and bypass channel - a similar picture is likely to be observed there.

To install a new regulator, be sure to remove the negative terminal of the battery. After assembly and connection, the IAC controller is calibrated - you need to turn on the ignition and wait 15 seconds. If the battery is not disconnected, the ECU will skip the calibration step, which may cause the engine to run unstable.

And let’s say, due to my inexperience, I won’t be able to understand how a minus coming from the ECU in the company with a minus on the body shows voltage, that’s what I wanted to know: if with the car running everything goes back to normal, that means the minus appears, so to speak, the sore appears precisely at the start, the voltage on both legs the same way. And if we have determined that there is no minus from the brains in the Ignition and Start mode, which leads to the IAC not opening, then where can we check this minus from the brains or is it Khan’s brains?

I'm about to start catching up, it turns out that the minus as such does not come from the ECU to the IAC, but sits somewhere in the brain and regulates the voltage that passes through from the overload relay through the IAC coil, so on the second leg the voltage value is less than at the input since it is driven down by the IAC coil. resistance?

The most common system withRXX(2 pin) . cars from 1987, usually equipped with a catalyst and an EZL electronic ignition system

System input signals :
- engine temperature,
- current air flow (signal from the flow meter potentiometer),
- engine speed (TD signal from the ignition system),
- state of the throttle valve (microphone “DZ closed” as part of the sensor on the DZ axis)
-signal from the speed sensor “sign of vehicle movement” (from 9/88)
Actuators:
- the idle speed regulator (hereinafter referred to as IAC) is an actuator that changes the amount of air passing bypassing the throttle to allow the engine to idle. XX control in KE is carried out by stabilizing air flow, and not engine speed. The controller memory contains a table of the dependence of air flow on engine temperature.

When the “DZ is closed” microphone is closed, the control unit (CU), based on the engine temperature, calculates the air flow that must be stabilized and, by controlling the IAC, tries to obtain such a flow. The ECU tries to stabilize idle only when the car is stationary, i.e. When driving in neutral, increased speeds may be observed, and only after a complete stop about a second do they drop to normal.
Those. if in the current operating mode of the engine (at hot t=90 degrees) the air flow is 0.7V, then the brains through the IAC will begin to close the damper (lower the speed), but not lower than 750, i.e. whichever comes first - either the air flow will become 0.6V, say at 750 rpm, or the rpm will drop to 750.

You need to understand that there is not an exact value of the stabilized air flow, but a certain range; there are also compensations in the presence of an automatic transmission, air conditioning, etc. (devices that increase the load on the engine, which requires compensation)
Over time, the coating on the potentiometer tracks in the XX zone wears off, and with the same deviations of the flowmeter shovel, the signal increases, i.e. if a new engine had 0.55V at 800 rpm, then by old age it can become 0.7V and higher, and therefore the rpm is always kept minimal (i.e., the system hits the lower limit - 700 rpm)...

Now about emergency mode: it occurs when the air flow signal ceases to satisfy a certain voltage range, then the system should stop regulating the idle and turn off the idle, but this cannot be done simply because the engine will stall (those who know the IAC device will understand), so the system increases the speed and de-energizes the regulator, without voltage there is always a 2mm gap - emergency window, (when starting it is fully open, then it is closed as the engine warms up). For the driver it looks like this: at first XX is normal, then suddenly the speed gradually increases to 1500 (emergency window in the regulator).
This can be simulated on a running engine by simply disconnecting the connector from the IAC
Examination

Measure both contacts relative to ground when the IAC is connected (lower the connector slightly, but do not remove). The motor is running, one will be about 12-14V , on the other, approximately 5V less. If there is no 12-14V on one of the contacts, check the overload relay.

More details

1. Regarding the ground, (black probe on the engine) we poke into both contacts. on one of them there will be 12V (same voltage as in the network). and on the other about 5V less. 2. Measure between your legs - 5V at XX of a warm engine.

Malfunctions

1. No power supply - you will not see tension relative to the body on either leg. Check the overload relay and the voltage in it.

2. On both contacts 12V, or between the legs 0V (both situations are equivalent) - there is no control of the IAC brain. For example, when the potential is removed, the Bosch ECU will have the following situation. There will be no VDO with the ECU.

The overload relay supplies battery voltage to one of the IAC terminals. Even without an ECU, it does. Those. When the ignition is turned on, at least one contact on the IAC must be positive . There is no plus - the overload relay does not give a plus (or the wiring).

The ECUs “control” the IAC by minus (weight). If your brains don't rule - there will be a plus on both terminals of the IAC (there is no mass from the brain).