VAZ 2109: fuel pump malfunction

VAZ 2109 fuel pump malfunction, types of VAZ gasoline pumps

On a VAZ 2109, signs of a fuel pump malfunction are a complete or partial cessation of the supply of gasoline to the carburetor, this entails the inability to start both a cold and hot engine, it will start and stall, in addition, unstable idling is possible. If you suspect that the fuel pump in the VAZ 2109 is not working, then you should check it. It's not difficult to do it yourself, just read this article.

Checking the fuel pump

So:

Let’s immediately look at the two most common types of gasoline pumps, “Pekar” and DAAZ. They are installed on both rear-wheel drive and front-wheel drive cars. To check the serviceability and functionality of the entire fuel supply system:
Remove the gasoline hose from the outgoing (discharge) fitting of the gasoline pump
Then press the fuel pumping lever manually several times
If the VAZ fuel pump is working properly, then a powerful stream of fuel should come out of the fitting
If there is no stream, or there is a weak stream, perform a second check

To check the serviceability of the intake valve:

We disconnect the fuel hose from the suction fitting of the pump (it turns out that now we have removed both fuel hoses from two fittings)
Then we plug the suction fitting with our finger and press the lever for manual pumping several times
At the same time, you should feel a vacuum on your finger (it should be sucked to the fitting)
When there is a vacuum, this means that the fuel pump is working, look for faults in the gas tank or fuel lines
If not, the fuel pump on the VAZ 21093 does not work, remove the pump, disassemble and change the intake valve

To check the exhaust valve for leaks:

Place your finger on the hole in the injection fitting (the one that supplies gasoline to the carburetor), then press the lever several times to manually pump
At the same time, a very noticeable stream of air comes out of the fitting hole, it pushes the finger away from the fitting
If the stream is weak or absent, it means that the fuel pump on the VAZ 2109 does not pump, then remove the pump, disassemble and replace the exhaust valve
If the filter is deformed or clogged:
Remove the cap from the fuel pump, take out the fuel filter, clean it, rinse it in gasoline, then blow it with compressed air
If the filter is deformed, then change it
In the Pekar brand fuel pump, as well as similar pumps, the filter is removed by unscrewing the suction fitting from the cover, so you don’t have to remove the cover itself
In case of malfunctions (leaky, torn) of the diaphragm:

A characteristic sign of such a malfunction may be the presence of fuel leaks on the fuel pump housing or the appearance of a gasoline smell in the engine oil. However, these signs may not appear:

Remove the upper part (cover) of the fuel pump housing
Take out his diaphragm assembly
Unscrew the nut on the rod, then remove the diaphragms (there are three in total)
Replace the diaphragms with new ones (you will need to purchase a repair kit)
Then put everything back together, the diagram is in the photo below

Scheme of the diaphragm assembly

The Pekar brand fuel pump has only one diaphragm.
It can be removed after removing the cover.
To disconnect the diaphragm assembly, rotate it 90 degrees.

If the valves are faulty, the VAZ 2109 does not pump the fuel pump, therefore:

Remove the cap from the fuel pump, as well as the fuel pump strainer.
Visually inspect the intake valve and fuel pump cavity
Remove the upper body, inspect the exhaust valve
When the valves are not pressed into the housing tightly or are not pressed tightly, or have lost mobility, then the pump must be replaced
If blockages are found, they should be removed and then the housing should be blown out with compressed air.
In the Pekar pump, both of its valves are located in the cover, so in order to assess their condition it is necessary to remove it from the body
VAZ 21093 fuel pump does not work, if the pusher is damaged:
Remove the fuel pump from the studs, while unscrewing the nuts that secure it
At the same time, its gaskets, heat-insulating insert and pusher remain on the engine
We rotate the crankshaft so that the pusher extends as far as possible
You should measure how much the pusher protrudes above the plane of the topmost gasket
The protrusion should be 0.8 - 1.3 millimeters
When the protrusion of the pusher does not fit into the given size, then you should try to adjust it by selecting shims of smaller or greater thickness (depending on whether the length is not sufficient or it sticks out strongly) or change the pusher
Replace only the outer thickest gasket located between the thermal insulation insert and the fuel pump
Although repair kits for fuel pumps with ready-made gaskets are sold, you can also save money and cut it yourself from a piece of paronite
If the spring under the diaphragm is broken:
It is necessary to remove the upper part (cover) of the fuel pump housing, then remove the rod with diaphragms, carefully inspect the condition of the spring
We replace broken, or compressed, lost elasticity

Checking and adjusting pump pressure

It's no secret that any car part has a certain resource. So the “nine” fuel pump, like any part, eventually stops pumping gasoline properly, our instructions will help you figure it out:

Moreover, on the VAZ 2109 the problems with the fuel pump are always the same
As a rule, the reasons are not tightness of the valves or housing, fuel wire, or diaphragm, perhaps the fuel filters are clogged, or the fuel supply lines are overheating
The main problem is ultimately insufficient gasoline pressure at the outlet of the fuel pump.
And in the case when your fuel pump initially could not show the appropriate (required) output pressure, then all the problems stated above only aggravate the situation
You need to know exactly the output pressure (immediately before the carburetor) that the fuel pump should develop when the engine is idling.
As a rule, all fuel pumps - both cars and trucks - must produce a pressure in the range from 0.20 atmospheres to 0.35 atmospheres. When your gas pump has a similar output pressure, then you should not have problems with gasoline supply
The pressure is measured with a pressure gauge that has a scale with divisions of 1.6 atmospheres - on such a pressure gauge it will be possible to record the pressure of the fuel pump
When the pressure is measured and it turns out to be below normal, you may just need to adjust the pump
It is possible to adjust the fuel pump either by moving it closer or further from the engine block (by changing the thickness of the gasket)
The second method is to strengthen the spring (washers are placed under it, the operation is performed taking into account the wear of existing parts and the strength of the spring)
The third option is to change the length of the rod
Any of the listed measures (or all in combination) make it possible to increase the pressure of the fuel pump to the level of 0.20 - 0.30 atmospheres
The best thing, of course, is to bring the figure to 0.30-0.35 atmospheres at idle speed
When the engine starts running at higher speeds, this figure will increase a little more.

Characteristics of the VAZ 2109 fuel pump

To understand how a working pump works and check its operation, it is important to know its operating characteristics:

The length of its rod is 82.4 millimeters
In this case, the rod protrudes above the gasket by 0.8 - 1.3 millimeters
The thickness of the very first gasket is 0.3 millimeters
And, the stroke of the rod is 2.5 - 2.8 millimeters

Useful tips

A couple of very useful recommendations for beginners on what to do if a fuel pump malfunction occurs on a VAZ 2109:

It is important to note that on machines with a return line, the problem may arise due to the release hole being too large, then most of the pressure is relieved by the return line
If the installed pump on your machine cannot be adjusted, you will have to replace it
Today, dozens of models of pumps for VAZ from different manufacturers are sold on the market.
In order not to buy a fake, you should approach the purchase very responsibly - choose a branded store and a reputable manufacturer, purchase only fuel pump models recommended by the VAZ plant
And the most ideal option is to contact an official VAZ spare parts dealer in your region, then you will receive the necessary part quickly, and you won’t worry about whether you got a bad quality fuel pump, and you won’t have to look for and buy a new pump a second time

Electrical diagram of VAZ 2110 features

Tuning Lada Vesta

Each VAZ-2110 car is equipped with electrical equipment, which is designed to ensure its operation and create comfortable conditions for the driver and passengers. All electrical appliances are integrated into a single network. To understand its composition and order of operation, an electrical circuit diagram of the VAZ-2110 was created. The on-board DC network has a voltage of twelve volts and includes energy sources and consumers, protective and distribution devices, wires and switching elements.

Current

The car has two sources of electricity - a battery and a generator. The first ensures the functioning of systems before start-up, during start-up and in some engine operating modes. The second is the main one and serves both to power all consumers and to charge the battery. The electrical circuit of the VAZ-2110 is designed in such a way that the power sources ensure energy balance in the system.

Motor

For the operation of the vehicle's power plant, timely supply of the fuel mixture and its ignition in the engine cylinders are necessary. On a modern car, this function is provided by the injection system. The electrical circuit of the VAZ-2110 (injector) allows you to correctly connect its two main components: the fuel distributor and the ignition control system. The injection is controlled by a special electronic unit. An uninterrupted supply of gasoline is ensured by an electric pump. It is installed directly in the fuel tank. The electrical circuit of the VAZ-2110 fuel pump is designed to meet fire safety requirements

Important note: Some brands of cars may have two fuel pumps installed. Previous VAZ car models used a carburetor fuel supply system

It is somewhat outdated, less economical and reliable. The electrical circuit of the VAZ-2110 allows you to connect a modern injector instead of the previous system without modifications. To change the fuel supply option, you must contact a specialist. For the engine to operate, its temperature must be maintained within the operating range. The cooling system is used for this purpose. It includes a fan and a number of sensors that operate on DC power.

Exploitation

A car is more than just one smoothly running engine. To operate this type of vehicle, lighting, alarm, safety systems (active and passive), sound signal, and windshield wipers are vital. This list can be continued. All named devices are consumers of electrical energy. There are hundreds of them in a modern car from the Volzhsky plant. And any of them can fail for various reasons. The electrical circuit of the VAZ-2110 allows you to diagnose and eliminate any fault that may arise, and replace electrical wiring elements. Modern traffic rules prohibit the operation of vehicles if the above electrical devices do not work.

Comfort

The electrical circuit of the VAZ-2110 includes a number of devices that perform a service function. That is, they provide minimal comfort for the driver and passengers of the car. These are air conditioning systems, interior lighting, also a cigarette lighter, power steering, and radio. Cars from the Volzhsky plant are not famous for their increased comfort. However, the electrical circuit of the VAZ-2110 allows for some modifications, that is, tuning. To carry out this work, the help of a specialist is required. The vehicle wiring is reliably protected by a fuse block (inserts). It is they who, when shorted, do not allow all the wiring to burn out. Use only original products of the specified power. Keep some spare fuses with you. If any electrical appliance fails, first check the serviceability of the fuse links. In most cases, replacing the fuse will resolve the problem. That's all the information we wanted to share

We thank every reader for your attention.

Correct procedure for disassembly and replacement

To remove the fuel pump, you need to perform the following sequence of actions:

Buy a repair kit right away, its price is cheap
Remove the air filter and its housing
Disconnect the fuel supply and return hoses from the pump fittings
Unscrew the nuts that secure it
We remove it carefully, as there is a possibility of damaging the gaskets.
Then you should inspect all the parts for cracks, check the tightness of all its valves
Make sure that the discharge and suction fittings do not rotate in their sockets
Diaphragms should not have peeling or ruptures
The filter must be undamaged and absolutely clean
Wash all its parts with gasoline and then blow them out with a compressor
After checking, replace all damaged parts; it is recommended to change the pump gasket as well.
When installing the gasket, apply lubricant like Litol-24 to its surface
If the housing is damaged or the main parts are irreparably damaged, replace the pump completely
Then you can proceed to installing it back
In this case, immediately adjust the feed using shims
And for this we measure the protrusion of the pusher
Since with a strong protrusion, increased gasoline pressure will be pumped, which will easily break the carburetor shut-off valve
In the case when the distance is lower than necessary, when the load increases and the vehicle speed increases, an insufficient amount of gasoline will flow into the carburetor
The procedure for installing the pump is the reverse of removal.
Also make sure that the arrow located on the body points towards the carburetor
When installing the diaphragm unit, it is important to place the holes in its gasket away from the muffler pipe

Here we have outlined more detailed instructions for removing and disassembling the fuel pump to make it easier for you to do it yourself if a fuel pump malfunction occurs on your VAZ 21093. We conclude here, there should be no difficulties; in addition, you can, of course, watch a video lesson on this topic.

The structure of the VAZ 2114 fuel system

The fuel system of the VAZ 2114 car consists of:

fuel module;
fuel lines;
injector ramps;
fuel injectors;
fuel filter;
fuel control systems.

The fuel module consists of the following elements:

fuel pump;
fuel level sensor;
float;
primary fuel filter meshes.

The filter mesh located on the suction pipe of the fuel pump has a fine-mesh structure, which allows it to trap contaminant particles that can damage the structural elements of the part. A fine fuel filter housing is additionally built into the gas pipeline system.

As a rule, the design of a fine fuel filter uses a material capable of retaining on its surface the smallest particles suspended in the fuel. The injector of a modern VAZ car is a fairly reliable device that provides control over the systems responsible for ensuring the smooth operation of the car engine.

The injector of a VAZ 2114 car, in addition to elements of the fuel supply system, includes an electronic control unit, as well as a large number of sensors that transmit information about the state of the car to the control unit and allow you to control the operation of the power plant.