VAZ 2109 starts and immediately stalls

Causes and manifestations

Carburetor malfunction can manifest itself in several factors in the car's behavior on the road. The first manifestation of such a problem is a situation where the engine stops working immediately after starting. This happens without the car moving, even when you do not press the pedals. But this is an aggravated manifestation. Sometimes the engine may function quite well, but the speed will drop as the load increases.

The causes of such problems may be:

Incorrect gasoline supply. If the fuel does not reach the float chamber, the following malfunctions appear;
The ignition turns off automatically;
Problems in the XX system;
Fuel filter clogged. Sometimes it just needs to be replaced;
A muffler malfunction that prevents exhaust gases from leaving the vehicle.

Idle air control problems

If a VAZ 2109 car starts up and the carburetor immediately stalls, then you should look at the idle air regulator. The nines use Solex carburetors. Such devices differ depending on the motor installed in the car itself. The engine can be 1.1 cm3, 1.3 cm3 and 1.5 cm3. If you compare their carburetor units in terms of external parameters, they will be almost identical. But their internal structure is significantly different. The filling will contain different jets, which differ in cross-section, and they also have spouts installed on the RUN. Other differences include emulsion tubes and diffusers. In VAZ 2109 cars, the idle system is responsible for stable engine operation at low speeds. Thanks to it, fuel is distributed normally.

The XX system includes the following components:

Special channels through which fuel and air are supplied;
Air jet;
EC, in which there is a special jet for fuel;
Speed screw;
A special needle that regulates the mixture of fuel and air that enters the carburetor.

The whole mechanism works as follows. The speed screw is responsible for the throttle valve changing its position. This flap should remain slightly open. This is necessary so that the fuel mixture can enter the internal combustion engine through the carburetor. It enters there under the influence of rarefaction. At the same time, it passes through the XX channels. The jets must be responsible for the correct dosing of this mixture, and the enrichment and integration is ensured by the adjusting needle. Fuel supply is controlled using EMG.

The problem is that the electric valve stops working. Because of this, fuel and air will not enter the special intake manifold. This leads to the idle speed simply disappearing.

You can try to lower the EMG a little, but this will not solve the problem. Yes, the speed will increase, but at the same time the amount of gasoline consumed will increase. But the problem will remain.

VAZ 2109 starts and immediately stalls - reasons and solutions

The VAZ-2109 model has a carburetor engine type. A Russian-made car that attracts buyers with its low cost, low fuel consumption, the possibility of quick and cheap repairs, as well as technical characteristics that satisfy Russia. But no transport is without weaknesses. The VAZ-2109 also has a problem - it starts and immediately stalls. The danger lies in the fact that the motor may stop working both while driving and when starting to move. What is the driving force and how to fix the problem? About everything in this article.

What to do

To understand what actually happened to the car, that its engine stalled, you need to conduct independent diagnostics and start with the fuel system. Problems with the supply of diesel fuel or gasoline to the engine most often lead to a sudden stop of the vehicle while driving.

The first reason is the fuel system and pump

Diagnostics consists of several stages, taking the form of a visual examination:

Checking the filling status of the tank with gasoline.
Fuel pump operation.
Filter cleanliness.
Cleanliness of fuel injectors.
The ignition system is working properly.
Serviceability of the electronic control unit.

Insufficient amount of gasoline in the fuel tank is the most common reason for engine stopping. Experienced drivers know that the gas tank level arrow readings should not always be trusted, especially when it comes to older models.

The second most common reason that requires appropriate diagnostics is failure of the fuel pump. As a result of a breakdown, the device stops pumping the combustible mixture into the engine. In addition to a visual inspection, the problem is also revealed by the characteristic buzzing sounds made by the pump’s electric motor, which it makes even after the ignition is turned off. Additionally, the condition of the device is checked using a pressure gauge - its readings must be at least 2.7 atmospheres.

A clogged filter means that even with a working pump, fuel cannot flow to the engine. The filter element of good devices does not allow even the smallest particles of debris to pass through, which are contained in almost any fuel, but as a result it becomes dirty quite quickly.

The cleanliness check is carried out using the starter turned on - it is activated by first removing the hose coming from the filter. If a stream of gasoline flows, everything is in order; when not, the filter element needs to be replaced. Not only the filter, but also the injectors can become clogged easily, especially if the fuel quality is average or lower. To diagnose them, remove the ramp and move it aside. Crank the starter - during normal operation of the system, the nozzles spray the combustible mixture. If there is no such effect, then the driver has encountered a breakdown.

The second reason is the ignition system

This is a problematic element in the car. When there is no spark, the engine will not be able to work. But more often it does not exist due to breakdowns of the wire or spark plugs, thanks to which a spark occurs and its strength is sufficient to initiate the operation of the power plant. Visually, on properly working spark plugs there is no deposit on the working surface and the gap between the electrodes is sufficient. Plaque or lack of clearance directly prevents the formation of a spark.

Faulty wires often have damaged insulation, causing current charges to flow from them to the crankcase. Check the formation of a spark by first unscrewing the spark plugs and placing them on the valve cover. Having done this, the starter is turned sharply and wait for a distinct spark to appear on the electrode of the spark plugs. In case of its complete absence, replacement of the latter is required.

The third reason is ECU problems

The electronic control unit is of particular importance for the proper operation of the engine, because its sensors in a modern car actually control the operation of each element of the system. Therefore, the failure of one or more such sensors leads to the inoperability of the power unit. If the previous diagnostics did not reveal other problems, then there is a high probability that a failure in the ECU is responsible for the fact that the car stalled. Particular attention should be paid to two sensors:

crankshaft rotation speed;
camshaft positions.

If any of them is faulty and does not give the required signal, the spark plugs cannot produce a spark. Also look at the contact connectors, which often fly out of their sockets while driving. To diagnose faults, you may need a special tester. You have a better chance of dealing with this problem if you contact a specialized service center.

Possible consequences of flashing the ECU

Using low-quality and untested software for the chip, you can add unsupported fuel supply, turbine boost, etc. circuits to the on-board device. The computer and car will malfunction. Carefully monitor and check the quality of the software used.

What to do if the problem is in the ECU?

The engine may not work correctly if the on-board vehicle malfunctions. At VAZ, he alone is responsible for the timely supply of fuel, synchronizing the operation of the injector nozzle and spark plugs. When the engine immediately stalls, this indicates a mismatch between the timing of the fuel supply and the ignition of the fuel mixture.

Usually, changing the firmware or restoring it to an industrial state helps. Although it may simply require adjustment of the fuel supply cycle, additionally the saturation of the consistency. In particularly difficult situations on a VAZ 2110 (or later model), you will have to replace the entire ECU unit or turn it off, switching the engine to manual operation only.

It should be noted that not only the ECU itself is responsible for the operation of the engine, but also a bunch of sensors that regulate the pressure in the injector, the saturation of the consistency, and the ignition timing.

In other words, it is necessary to check their operation. Although, if a textbook malfunction is detected from among them, a Check Engine signal should be sent to the dashboard. This, for example, happens when a VAZ 2110 starts up. This does not happen only in this case if the ECU simply does not receive signals from the sensors. It is worth noting that the model 2107 usually does not have a computer installed, but the injector does not work without it.

Identical problems arise when the carburetor is synthetically converted to an injector, but the same side panel is retained. In a personal computer, they simply change the firmware, connect new modules, alas, you need to realize that at first it is not designed for similar work. Thus, if the carburetor is rebuilt, then along with its help it is necessary to change the ECU to a compatible model. Fantasy, VAZ took care of their release.

What is needed, if the injector starts and then stalls, then the main reasons for such a malfunction are disturbances in the operation of the electronics (including the ECU), incorrect operation of the fuel system that allows for accounting (software) or problems with filtering gasoline. Identifying the root cause is not a problem. In the latter case, you can always contact center 100. Unfortunately, it is worth keeping in mind that any adjustments to the operation of the on-board vehicle, of course, can only be made if the engine is in good working order.

VAZ 2109 starts and stalls

Winter has come, and with it came frost. One such morning I start my VAZ 2109 in the morning, it picks up perfectly, starts and works. I think everything is fine and am about to go out and clear the snow from the car, but it suddenly stalls. I'm trying to start it, I turn the engine with the starter - it doesn't even catch. I check the spark, there is a spark. I unscrew the spark plug and it is dry. It’s clear that there is no gasoline in the carburetor, probably the needle is stuck, or the floats are frozen, I think. I remove the supply and return hose from the carburetor, plug the return hose fitting with my finger and blow with my mouth into the supply - air passes through, which means the needle is not closed and gasoline should flow into the carburetor. All that remains is the fuel pump.

Fuel pump VAZ 2109

I put a small plastic bottle on the gasoline supply hose from the fuel pump and turn it with the starter. Empty, the pump does not pump fuel from the gas tank to the carburetor. It’s strange, I think, and I try to pump the fuel pump manually - it pumps. And it pumps well. I crank the engine again with the starter, the fuel pump starts working. Further, a similar nuisance that the car starts and stalls occurs to me periodically a couple of times a week. Naturally, I’m not very happy about this and am trying to figure out what’s going on. Moreover, the nine senses when I’m in a hurry somewhere, or I’m driving someone, and it starts and stalls at the most inopportune moments. This only happens when the engine is not warmed up, after a day in the cold. The reason that the engine starts and stalls is that the fuel pump does not want to pump gasoline when the car is not warmed up. I had an answer to this problem by reasoning: “If the manual pumping works, then the fuel pump itself is working. However, why doesn’t he pump himself?” As always, everything is simple: because the pusher stroke of the fuel pump is insufficient. Plus, due to the frost, it is covered with frost and does not move forward or backward.

Operating principle of the fuel pump pusher

This pusher is driven by an eccentric on the camshaft and returned back by a spring. The fuel pump pusher is sold at any auto store; if you visually see that the pusher is worn out, you need to replace it.

Unscrew the fuel pump Remove the fuel pump gasket Take out the fuel pump pusher Remove the pusher rod

Do not buy a pusher anywhere, for example, at car markets and from dubious sellers. If you purchase a low-quality pusher, you will very soon encounter the same problem again. The fuel pump pusher is made of high-quality steel and practically does not wear out during operation. I know cases where people purchased a fuel pump pusher on the market, and then it turned out that it was just a nail of the appropriate length and diameter. And if the pusher is not worn out, then its stroke is regulated by selecting sealing gaskets, which can also be purchased at the store. The normal stroke of the pusher from the gasket surface is 0.8-1.3 mm.

Finding the faulty component

What do you need to do if the engine just starts, but then immediately slows down and stalls? First, you need to check for carbon deposits on the spark plugs. If some models are covered with a layer of carbon deposits, then the engine a priori does not have the right to work normally. It first starts by moving the starter, but then immediately slows down, because several cylinders at the physical level are not able to withstand the entire load from the crankshaft. The carburetor, in some cases, can also fail due to this problem.

So what is the cause of the motor malfunction? If the car starts, then, no less, with a spark, what remains for our client to do normally. In other words, the electrics work as expected. It will be useful to unscrew the heads and try to find those candles that are covered with a layer of soot. There is an option to clean them by burning them over a gas burner and cleaning with alcohol (do this, of course, only when the contacts are cool).

The injector itself

It can also get clogged. The supply of fuel to the combustion chamber simply does not work. The following actions should be performed:

remove the blocks and check the valves;
check the operation of the sensors;
check whether the engine operates normally at temperatures above 80ºС.

Malfunctions due to air entering the fuel system

The problem can also occur due to improper operation of the fuel system. As a result of its malfunction, the air supply may increase, which will lead to a too weak fuel mixture. The fuel will not be able to burn normally in the cylinders, which is why the VAZ 2109 starts and immediately stalls.

There may be several reasons for this problem:

First of all, this can happen due to damage to the carburetor. Then air will be sucked in in the area between the cover and the body of the device;
Due to the fact that the lower platform of the HRSG does not fit well to the collector;
If the connection in the VUT is broken. This may occur due to a ruptured hose;
If the vacuum booster is completely faulty.

First of all, you need to check whether the vacuum booster is really faulty. To check this, you just need to disconnect its hose from the intake manifold. Next, you will need to plug the fitting and start the car.

If the problem lies in the vacuum booster, then this can be easily determined by the operation of the engine after the manipulations have been performed. If it starts to work better after plugging the fitting, then the problem really lies with the VUT. If you see air hissing in the area of the vacuum booster, or the engine begins to lose speed when you press the brake pedal, then the problem is an air leak. This malfunction can also occur if the EMR diaphragm is broken. Check this part by simply unscrewing a few screws on the installed carburetor. If necessary, it will need to be replaced.

21099” Stalls

Previously it stalled when I pressed the accelerator pedal, at the moment. almost immediately

after the launch, the rest is on video.

Perhaps the fuel pump itself could be faulty. When the engine is started, the injector turns automatically due to the use of a starter, and then the thrust comes from the generator. If one of these components does not work correctly, the car will simply stall . Here again we are talking about the residual amount of fuel in the cylinders. On the contrary, the engine immediately stalls, and together with its help the starter also works unevenly, then, most likely, there is a problem either in the personal computer, in other words, in the ignition switch

The accelerator pump is faulty

The accelerator pump can also lead to similar malfunctions. If you notice poor speed gain, engine shutdown, dips and other problems, then this means that you should pay attention to this system.

The main causes of malfunction in the nine:

A malfunction may occur if the sprayer is dosed incorrectly. This may also be due to a clogged spout or elephant channel;
Problems with the diaphragm (ruptures, drying out);
The cause of the malfunction may be that the accelerator pump flag was incorrectly selected.

On sprayers that were installed from the factory, you will notice two spouts. Each of these spouts distributes fuel into 2 chambers. This is the primary chamber and also the secondary one. Many mechanics believe that fuel injection into the secondary chamber is completely unnecessary. Therefore, the sprayer is often modified. Its essence lies in the fact that both spouts are connected to the primary canal.

There is one peculiarity here. During this modification, it is necessary to make the installation of the tubes at a bend so that the injection passes correctly into the primary chamber. With proper injection, the fuel should pass smoothly between the carburetor body and the choke. If fuel gets on them, there will be no effect.

To check for correct installation, you will need to remove the carburetor. You will also need to remove the top cover from the carburetor and fill the float chamber. When the throttle valve opens, gasoline must flow between the parts.

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How to help the engine work

Sometimes the VAZ 21099 carburetor does not start well. To help a cold engine work, you need to perform the following steps.

Press the handle of the fuel pump to pump gasoline into the carburetor float chamber.
Place the gearshift lever in neutral position.
Pull the choke toward you, closing the throttle valve, and with the ignition on, try to crank the starter. If unsuccessful, repeat the action after some time.
If the car starts, let it idle, release the throttle and take your foot off the clutch pedal.
In the cold season, try to turn the crankshaft several times, turn the headlights on and off, pull out the choke handle, squeeze the clutch and turn the starter. In winter, to keep warm and improve engine performance, it is recommended to wrap the radiator grille. When the engine starts, the pressure control and battery charging lights on the operating panel should go out.

The driver starts the car

When the car is warmed up, its engine should start running immediately. Other situations arise when the machine does not. Starting a hot engine should take place with the throttle valve open and the gas pedal depressed to one third of its full travel. As soon as the engine starts, you need to release the accelerator pedal. If the start is unsuccessful, repeating the described steps may lead to difficulty starting the engine and flooding the spark plugs with gasoline. If this does happen, the turned out candles must be dried with air.

Malfunction in carburetor models

If this malfunction occurs in cars with a carburetor engine. This is primarily due to the lack of fuel in the float chamber. Typically, in this case, fuel is pumped into the fuel pump manually. If the fuel pump is damaged, it needs to be replaced.

Another important reason why the engine stalls is a clogged strainer in the carburetor. In this case, the car stalls a few seconds after the starter is turned on.

To eliminate this problem, you need to thoroughly rinse the filter in acetone using a special brush. After the procedures, you also need to clean the connector in which it was located.

It happens that after starting the car, its speed drops, as a result of which it stalls. In this case, the problem is a faulty solenoid valve. This is checked as follows. First, you need to unscrew the valve, then apply power to the positive contact, and short the housing to engine ground. If the valve is corrected, a characteristic sound will be heard. If there is no sound, the valve does not work. In this case, you need to remove the jet from the valve and replace it if it is deformed.

If troubleshooting did not lead to the desired result, but the problem occurs again (especially in the cold season), then you need to help start the engine manually. To do this you need to follow these steps:

Press the handle of the fuel pump and pump gasoline into the carburetor float chamber.
Place the gearbox in neutral position.
Pull the suction towards you. You need to close the throttle, turn on the ignition and start the car.
After the car starts, you need to keep it running at idle speed.

To improve engine performance in winter, it is recommended to cover the radiator grille with a special cover.

You need to understand that the search for an answer to the question: “Why does a car stall in different conditions” often varies greatly within the same car. There are a lot of differences, all of them are divided based on the specific situation and options for using the car.

Of course, the easiest way to solve this problem is to contact a specialist. In this case, you can save a lot of time and effort, and most importantly, it will deprive the owner of unnecessary headaches.

But despite this, there is no single advice for all car enthusiasts. There are only recommendations that you can follow to avoid this kind of trouble.