A small element attached to the body throttle valve, is also the cause of engine failure with such symptoms on VAZ-2112 cars. The thing is that when the throttle position sensor is faulty, it is not able to transmit the command to open in time idle move. Thus, the system thinks that the driver continues to press the gas pedal, making the air supply minimal. Based on this, it starts again after another turn of the key.
The sensor is located here
Ignition system
First we check the wires, and then the spark plugs.
Supply system
In this case, check all the wires coming from the battery, generator and. Since even the slightest short to ground of the power wires can shut down the engine.
Fuel pump and grid
It is possible that a large amount of deposits has formed on the grid, which is located directly in the gas tank, and while driving the required amount of fuel simply does not reach the engine, which causes the engine to stall. Requires cleaning or.
Idle speed sensor close up on an editorial VAZ-2112
Although such a cause of malfunction is not inherent in this sensor, however, it should not be ignored. If there are deposits on it, then it should be cleaned; if there is mechanical damage, then replace it. About how to do it correctly.
Results and conclusions
If all the above reasons do not help you, you have a chance to seek help for a professional diagnosis. Since the departing " check engine", will still indicate the cause of the malfunction and replacing this element will cost a lot.
If somewhere along the way your VAZ 2112 stalls, starts up briefly, and then turns off again, then it is unlikely that you will be able to fix the problem in the field. Although there are no rules without exceptions, it happens that the tank simply runs out of fuel, and the sensor is lying. But oddly enough, it is much easier to detect a breakdown in a car when it shows no signs of life. Whether it will be possible to revive him on the road is a difficult question, but it’s worth a try. There are several recommendations.
What could have broken?
If the machine does not work, it means the motor is broken. This can often be heard from an inexperienced driver. But in a car, in addition to the engine, there are many different elements, on the serviceability of which the operation of the power unit depends. If the car is not completely “dead” and when the starter rotates, it shows signs of life, “sneezes” or “shoots” at exhaust pipe, the fault will be more difficult to find.
The malfunction that led to the engine shutdown is hidden in one of the three systems of the VAZ 2112:
- electrical equipment and power supply;
- fuel supply system;
- gas distribution mechanism and piston group.
You must understand that if the level of coolant or oil in the crankcase is low, the engine will not stall; it may fail due to overheating or lack of lubrication. Therefore, it is important to recall the circumstances preceding engine failure. It's one thing when power unit just stopped while moving, another thing - if before that you heard extraneous knocks or shots in the exhaust. In the first case, the electrical part is probably to blame.
A sign of the second situation is often a broken timing belt, which is easy to detect by removing its upper plastic casing. The belt can be changed on the way if you have a spare one, otherwise you will have to look for a part or a towing company. If the starter cannot crank the engine when trying to start, there may be two reasons:
- there was a breakdown in the generator circuit, and the voltage source was the battery, which as a result was discharged;
- the crankshaft jammed due to lack of lubrication.
In both situations, you need to find a way to deliver the car for repairs; you won’t be able to do anything on the road.
Electrical faults
There are several reasons why the engine may stall:
- ignition switch malfunction;
- the fuse in the fuel pump circuit has burned out;
- no voltage is supplied to the spark plugs;
- one of the sensors on which the operation of the power unit depends has failed.
First of all, it is recommended to check the operation of the fuel pump; when the ignition is turned on, it emits a quiet hum (coming from the rear of the car). When there is no such sound, it is necessary to open the VAZ 2112 fuse box and check the condition of fusible link No. 3, which closes the fuel supply relay circuit. The blown fuse must be replaced with a new or temporary “bug” made of copper wire and try to start the engine. If the car starts, feel free to continue on your way.
Without knowledge of the electrical part of the car, a breakdown of the ignition switch cannot be avoided, and it is not easy to diagnose it. Therefore, it is recommended to check for a spark on the spark plugs, for which you need to unscrew one of them and securely attach it to a metal part of the engine by connecting a high-voltage wire. Then turn on the starter and watch for sparking. If there is a spark, good, we need to look in a different direction. If it is not present, the following breakdowns may occur:
- the simplest thing is failure of high-voltage wires or spark plugs;
- malfunction of the ignition switch or the corresponding relay;
- the switch or ignition distributor slider has become unusable (on carburetor cars);
- The position sensor is faulty crankshaft(on cars with an injector).
If high voltage wires or the spark plugs can be replaced, then the breakdown of the remaining elements must first be accurately diagnosed, which is hardly possible in the middle of the field. In addition, the throttle position or air flow sensor may break, causing the controller to switch the injector to emergency mode work. Then the car may often stall at idle.
Fuel supply problems
The reason that the engine stalls at idle may be not only the fuel pump, but also a fuel filter that has not been changed for a long time.
If the element is completely clogged, then the amount of fuel passing through it is simply not enough for the normal operation of the power unit.
In carburetor VAZ 2112 models, the cause of a lack of fuel may be wear of the mechanical drive of the fuel pump or its diaphragms. It's easy to check: disconnect the fuel supply hose from the carburetor and direct it to plastic bottle, then turn on the starter. The stream of gasoline from the hose should be powerful and steady; when gasoline flows weakly, try temporarily removing the gasket under the mounting flange of the fuel pump.
The lack of fuel in the carburetor is checked by removing the air filter cover and pressing the accelerator rod. A stream of fuel should spray from the nozzle nozzle exiting into the primary chamber of the carburetor. When it is not there, you need to clean the strainer installed at the inlet of the unit, or check the operation of the needle valve.
As for the injector, it is unrealistic to detect faults with the fuel supply on the road. Even if you manage to get to the injectors and unscrew them, you will not be able to check. In order for the injector to supply fuel, it must receive a signal from the controller. Only an experienced electrician can create such a signal artificially, so disassembling the injector on the way does not make sense. It will be difficult to find the reason for the lack of a spark, which may be hidden in the ignition module or in the coil. You can find out more precisely only at a car service center.
At one time it takes a long time to start, but then it starts with difficulty, and at another time it may start the first time and immediately stall. What could be the reason for this behavior? There is no difference, what, what.
Such a problem as: the engine stalls at idle speed can be heard quite often. And even if after some period of time the engine does start, the cause of the malfunction will have to be looked for one way or another. And the sooner the better, because there may be several of them.
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All my life I have been surrounded by cars! First, in the village, already in the first grade, I was rushing around on a tractor through the fields, then there was JAVA, then a penny. Now I am a third-year student at the Polytechnic Faculty of Automotive Engineering. I work part-time as a car mechanic and help repair cars for all my friends.
The video below shows an example when a VAZ-2112 stalls at idle:
Reasons why the engine stalls
Location of the throttle valve on a VAZ-2112 - photo of an editorial car
Signs and solutions to problems
Below we will look at the most common signs when a car stalls at idle.
The car starts and stalls immediately after the starter is turned off.
The car starts and immediately stalls
Checking the MAF sensor readings
The cause of a malfunction with such symptoms is most often the above-mentioned sensors: IAC (idle air control), MAF (mass air flow sensor). Before purchasing new parts, you need to disassemble them and check for contamination. Also . However, if you have the opportunity to check the malfunction on diagnostic equipment, then don’t deny yourself this. Read more about replacing the mass air flow sensor here.
The functionality of all sensors should be checked in order, starting from the least structurally complex to the most.
A malfunction in which a car The VAZ-2112 stalls a couple of seconds after starting the engine, giving the driver a lot of negative emotions. But in order to find the cause of this malfunction yourself, you need to know why this can happen. If you do not have this knowledge, then there is only one way out, go to good specialists who can diagnose the engine.
The first cause of this malfunction may be idle air control(IAC), which is located on the throttle assembly. You can make sure that it is he who is causing the malfunction as follows. Open the hood of your VAZ-2112, look for air filter, between it and the intake pipe hose, a mass air flow sensor (MAF) is installed.
You remove the terminal from it and try to start the engine of your car. If the engine starts and, with the gas pedal released, keeps the crankshaft speed in the region of one and a half thousand, this will mean that the idle speed control is in working order. Since it is he who maintains such speeds at removed terminal from the mass air flow sensor. A similar check can be carried out when removing the terminal from the throttle position sensor (TPS). It is located on the side of the throttle body pipe.
If the engine, during these two checks, also starts, and then immediately stalls, then the idle air control valve or the wires going to it may be to blame. But in order to pass a final verdict on it, you will need to check the condition of the throttle assembly, since it has a tendency to become dirty, which prevents the rod from moving. In this case, even a working idle speed controller will not be able to perform its intended function of regulating the engine crankshaft speed.
If it turns out that the idle air regulator is to blame for this malfunction, and you purchased a new IAC, then before installing it instead of the faulty regulator, you will need to turn off battery, by removing the negative terminal. Time the removal of this terminal and begin installing the new IAC. If you did this work quickly, then put the negative terminal back in place no earlier than 20 minutes from the moment it was removed. Next, turn on the ignition and keep it on for about twenty seconds. Then turn off the ignition and only after these steps do you try to start the engine of your car. This is done in order to reset the settings electronic unit control (ECU), otherwise it will issue this error again.