The engine starts and immediately stalls: the causes

Probably, there is not a single owner of a domestic car that would never be in a situation where the engine of his car refused to start. A similar problem is familiar to drivers of foreign cars, but our cars suffer this "disease" much more often.

. Often happens and so that the car starts and immediately stalls . There can be many reasons for this. About them, we'll talk in this article on the example of the car "VAZ-2109" with carburetor and injector engines.

Everything you need to start the engine

To start and stable operation of the gasoline engine, regardless of the type of power system, it takes only two things: a good timely spark in the cylinders and the flow of fuel mixture into the combustion chambers. In the absence of at least one of these components, all your attempts to start the motor will be in vain.

Since it is much easier to perform a preliminary check of the ignition system than the power supply systems, the diagnosis begins with it.

Check the presence and condition of the spark

Determine whether the voltage is applied to the spark plugs is not difficult. It is enough to unscrew one of them, connect the central electrode to the corresponding high-voltage wire, ensure the contact of its "skirt" with the "mass" of the car, turn on the ignition and start the starter. If a stable spark of blue or white-blue color is observed on the spark plug electrodes, everything is in order with the ignition. Of course, it will not be superfluous to check all the candles in the same way. , является неисправность одной или нескольких свечей. The fact is that very often the reason that the car starts and immediately stalls is the malfunction of one or several candles. At first the engine starts and tries to work on three or two cylinders. This process is accompanied by a characteristic "rolling" and increased vibration of the power unit. Having worked a little at idle, the engine is sure to stall. Cylinders with non-working candles are filled with gasoline. On restart, everything repeats, i.e., the motor starts to "grasp", but after a few seconds it stops working.

If the spark is on all the candles, pay attention to its color and size. . If it has a yellow or red color, and its size is incommensurably small, in comparison with the interelectrode gap, it can also be the reason that your car starts and immediately stalls .

This problem is solved by replacing non-working candles. When buying them, do not forget to comply with the requirements of the manufacturer concerning the glow number and clearance.

Diagnose high-voltage wires

как и прежде, стоит проверить высоковольтные провода. If you determined that everything is in order with the spark plugs, and the VAZ- 2109 starts and immediately stalls, as before, it is worth checking the high-voltage wires. In view of the constant stresses created by high voltage, they also often fail. The fault of the wires is the violation of the integrity of the conductor or insulation. In the first case, electricity does not flow to the candle, so the spark disappears. If there is insulation damage, there is a breakdown between the live conductor and the "mass" of the car, that is, part of the electricity simply goes away. Because of this, the spark loses its power, and often also the ability to ignite the fuel mixture.

The high-voltage wires are checked in the same way as the candles. In addition, the resistance of the conductor is measured. Depending on the brand and model of wires, it can be from 0.4 to 0.9 kOhm.

Feasibility of further testing of the ignition system

? You checked the candles and high-voltage wires, replaced the faulty elements, but the "nine", as before, is wound up and immediately stalls ? There is no sense in checking the ignition coil and the switch. Usually these ignition elements either work or do not work. In other words, if there is a steady spark in all cylinders, the cause must be sought in the fuel system.

Sensors of the power supply system of the injector motor

, но при этом с зажиганием все нормально, первым делом обратите внимание на панель приборов. When the engine of your VAZ (injector) starts and immediately stalls , but with the ignition all right, first of all pay attention to the dashboard. All problems of the power unit are fixed by the electronic control unit, which the driver is notified with the CHECK warning light. In this case, it is desirable to immediately test the device and determine the fault by the error code. But if this is not possible, check the mass air flow sensor (MFR) and the idle speed regulator (РХХ).

. Often it is the faulty DMR that causes the injector "nine" to start and immediately stall . This sensor determines the amount of air flowing through the duct to the intake manifold. Based on his data, the electronic control unit regulates the concentration of the fuel mixture. The slightest malfunction of the mass air flow sensor leads to its incorrect formation. As a result, we have an increase in fuel consumption, floating idling speed, problems with starting the engine.

Well, and how not to mention the regulator (sensor) idling. It is he who receives the signal from the electronic control unit about the necessary amount of air for the combustible mixture and mechanically increases or decreases its volume. The regulator takes a direct part in starting the engine and its operation during the warm-up phase in idling mode. , не забудьте проверить и РХХ. So if your car starts and immediately stalls , do not forget to check and РХХ.

Verification of the DMRM

To diagnose a mass flow sensor, we need an autotester or a multimeter. The DMVB is located on the duct going from the filter to the intake manifold. To start, start the engine and warm it up to the operating temperature. Pay attention to its speed. Now disconnect the harness harness from the sensor. The motor should react to this by increasing the number of revolutions to about 1500 rpm. This computer has activated the emergency mode of operation, in which only the information received from the throttle position sensor is taken into account for the formation of the fuel mixture . If the operating mode of the power unit has not changed, most likely, the DMRW is faulty. To verify this, use a multimeter, included as a voltmeter with a measurement limit of 2 V. In the car we turn on the ignition, but the motor does not start. The red test lead of the multimeter is connected in the shoe to the yellow wire of the DMRV, the black one to the green one. We look at the readings of the device. At the good sensor, the voltage between its terminals should be 0.996-1.03 V. If it exceeds 1.05 V, the device is definitely useless.

PXX check

To check the idle speed regulator, use the multimeter, included in the ohmmeter mode. PXX must be disconnected from the onboard circuit before starting the diagnosis. First of all, we measure the resistance between terminals A and B, after C and D. It should be within 53 Ohm. Next, measure the resistance between A and C, B and D. Here it should tend to infinity. If the test results differ from the values given, the regulator is defective, and most likely it is he who is guilty that your car starts and immediately stalls. выхода РХХ из строя может заключаться либо в обрыве одной из обмоток, либо же в износе направляющих конусной иглы. The reason for the failure of PXX can be either in the breakage of one of the windings, or in the wear of the guide cone needles. In any case, it is better to replace it.

Possible malfunctions of the carburetor

And now let's talk about the problems with the launch of the carburetor engines of the "nine". There are no sensors that affect the operation of the power system, but this does not mean that there are less problems with them. тому причина. If you are sure of the serviceability of the ignition system, but your car starts and immediately stalls - the carburetor is the reason. Rather, one of its working elements, responsible for the engine at idle.

It is recommended to start the test from the solenoid valve of idling. 2109". This device more often leads to the fact that it is started and immediately stalls "VAZ- 2109". It does not matter which carburetor is installed on the engine.

The easiest method for diagnosing the valve is to disconnect-connect the device to the power cord with the ignition on. The clicks that occur when the positive wire is connected to the corresponding terminal indicate that the electromagnet is working properly. If the valve does not react to the supply of electricity, you can safely throw it away. Naturally, having installed a new one in its place.

Having unscrewed the solenoid valve, check at the same time and a condition of a fuel jet of idling. If necessary, purge and rinse with a carburetor cleaning fluid. The clogging of the idler also affects the operation of the engine without load.

To problems with the launch of the power unit leads and sucked into the system of excess air. As a result, the fuel mixture is depleted, and the engine starts to work intermittently, losing speed and power. Check the tightness of the system in the area where the vacuum tubes to the trampple and the brake servo are attached, as well as the idle seat.

The car gets into a frost and immediately stalls

Low temperature can affect the stability of the engine only when the fuel pump is faulty. You try to start the engine in a severe frost, it starts, but after a few seconds stalls? Try to pump fuel through the pump lever. If the situation has changed, look for the problem in the pusher. In addition, that its gaskets can be worn, which, moreover, become stiffer in severe frost, and it can itself become covered with hoarfrost. All this makes it difficult for him to move. As a result, fuel in the carburetor arrives in a smaller volume, which, again, leads to depletion of the fuel mixture.