Why the engine stalls at idle: the causes and solutions to the problem

Any self-respecting car owner should monitor the serviceability of his car and maintain it in good technical condition. But sometimes there are problems with the start and operation of the power unit. For example, the engine stalls at idle. What is the reason for this phenomenon, how to deal with it? About all this we will tell in our today's article. Before giving an answer to the question of why the car stalls at idle, we note that all problems will concern faults with the supply of a fuel-air mixture.

If it's a carburetor?

On old cars with a carburettor intake system, with such symptoms, the automatic throttle breaks down. This element "sinks" or is poorly adjusted. If stalls at idle VAZ-2106, the malfunction may be accompanied by a leak from the vacuum hoses near the base of the carburetor. Do not rule out problems in the cooling system. If the machine stalls at idle, check the condition of the thermostat. With a faulty valve, the mechanism does not allow the engine to quickly warm up to operating temperatures. In the summer, the car often boils.

In detail about the inlet system

Since the engine needs not only gasoline, but also oxygen, the speed problems concern the intake manifold. Such troubles are due to the sucking of air in the place that comes after the filter. As a result, the sensor of the air flow meter is not able to control the process, and the machine stalls at idle.

The injector is often equipped with DMRV. Do not overlook it. Often this sensor is contaminated through 100-150 thousand kilometers. It can not be repaired - just replace it. It is worth this detail is inexpensive, but it is because of it, in most cases, floating turns on idle. The engine also dies due to fuel injectors. It is worth checking the state of the injector. If it is clogged, the crankshaft turns will be unstable. The combustion chamber receives a different amount of the combustible mixture, which contributes to improper operation of the ICE.

Filters

At run in 10 thousand kilometers it is necessary to change the air filter. It is located in a plastic or metal casing (on injector and carburetor motors respectively). If this element looks like the image below, it should be replaced.

But not only the air is purified in the system. Pay attention to fuel filters. On diesel engines, they change every 15 thousand kilometers. As for cars with gasoline engines, they are serviced every 50 thousand. The throughput of these elements is 10 microns. If low-quality gasoline or diesel was used, the internal parts of the filter are quickly clogged. Inside is a porous paper.

If there is a lot of dirt, the element is no longer able to clean the fuel. As a result, the car does not hold idle turns, stalls. It does not even save that the pump runs under high pressure. When the filter is heavily clogged, it must be urgently changed. The replacement feature is also power loss and dips in dynamics.

The difference between carburetor and injector filters

It is worth noting that the level of pressure in these intake systems is different. He has many times more injectors. Therefore, when buying new fuel filters, you should check with the seller exactly which motor you have. Especially it concerns cars, on which different types of systems were installed (for example, old and new "tens").

If you put a filter on the injector engine , designed for the carburetor, it simply does not stand the pressure. All dirt gets into the injector pump. They are clogged, so the motor stalls at idle. As for air filters, it is very easy to distinguish them. In carburetor motors, they have a circular shape.

"Nullivi"

If a zero-resistance filter is used in the machine, if it is heavily soiled, it can cause problems in the engine operation. But the cost of such a cleaning element is 7-10 times higher than that of conventional cleaning elements. Therefore, special sprays are used for their purification. Filters are processed every 10 thousand kilometers. After applying the formulation, you should wait until it is absorbed, and rinse the "zero" with water for 5 minutes. Before installation, carefully dry it. Otherwise, when you start the machine will catch a hydro shock.

Pumps

If the car stalls at idle, the cause may be covered in low pump pressure. On the injector engines it is submersible and is located in the fuel tank itself. On carburetor motors, this element is located separately from the tank and refers to a mechanical type. Such a pump is activated by means of a handle. It is she who creates the right pressure in the system. But if the fuel line is clogged, submersible and mechanical pumps do not work at full capacity. As a result, the car stalls at idle.

If the car does not start at all, it's worth checking the power supply for the element. Look at the fuses and relays. If the pump does not hum on the injection motor when the ignition key is turned on, it means that no power is supplied to it. On passenger cars it is located in the rear of the cabin, on the right (under the passenger sofa). If it is a diesel power unit, it is worth checking the high-pressure fuel pump. At negative temperatures, paraffin is accumulated in it - frozen particles of diesel fuel. There are problems with starting the engine, the revolutions often "float". Do not exclude and mechanical failure. The cam drive may be out of order.

Electronics

If the car stalls at idle, it is necessary to diagnose the on-board computer. If there are errors in programming, there is an incorrect mixture formation. Because of this, the motor starts to malfunction. This happens when you turn on additional electrical appliances (for example, air conditioning). Exit from this situation is a flashing of the electronic control unit.

Catalytic converters

With the increase of environmental standards, so-called soot filters began to be installed on diesel cars , and catalysts were used for gasoline ones. They are designed for a certain period of operation (about 150 thousand kilometers). Over time, the core is clogged. The device can not produce a normal exhaust and purify the exhaust gases.

The way out of this situation is the replacement of the catalyst with a flame arrester and a rewiring of the electronic unit. But at the same time the exhaust rate of your car will drop to the value of "Euro-1". In the countries of the European Union, the exploitation of such vehicles is prohibited. But if you drive mainly in the CIS, this is the most optimal solution to the problem. After all, the cost of a new catalyst and particulate filter starts from 40 thousand rubles.

The valve of recycling

The machine can stall for idle due to faults in the exhaust gas recirculation system. With computer diagnostics, the screen displays the error "P1406". It indicates that the valve is "stuck" in an open or closed position. The car stalls at idle and shows a weak dynamic on high. Over time, this flap accumulates plaque. You must unmount the element and clean it. But if the symptoms are repeated during the re-installation, only replacement will help.

Absolute pressure sensor

This mechanism measures the vacuum in the manifold to adjust the amount of feed mixture. A defective element misleads the engine. The ECU thinks that the motor runs under a much smaller or greater load than it actually is. Thus, the control unit removes a certain amount of fuel. The machine starts to stall. The way out is to replace the absolute pressure sensor. So, we found out for what reasons the car stalls at idle.