The petrol pump does not work: possible causes and solution of the problem

By itself, gasoline (diesel fuel) from the tank of the car to the engine can not get, it requires a pumping mechanism - a fuel pump. And if it fails, the consequences are predictable - the machine will rise. Possible reasons for this may be a lot, and since they are typical for almost any brand of car, it is better to talk about them in a specific example. Let's say that the VAZ-2110 petrol pump does not work.

Types of fuel pumps

Serial production of the "dozen" began in 1995, that is, at a time when domestic cars were equipped with carburetor systems. In them, for fuel transfer, petrol pumps (pumps) of a mechanical type were installed. This pump functions directly from the engine of the car.

The carburettor does not need high pressure to function properly, therefore the pump has a relatively simple design, similar to water pumping systems. It is installed directly under the hood of the car, which, of course, facilitates its maintenance or replacement.

With the advent of injectors, the design of the gasoline pump was also modified, it became electric. The principle of his work has also changed. If it is required for the operation of the mechanical pump that the starter starts to rotate the crankshaft, then in the injector system the fuel pump is first energized, which by means of the built-in electric motor generates the required pressure in the line, and only then the engine starts.

This type of gasoline pump is installed directly into the fuel tank.

Thus, there are two types of fuel pumps: mechanical and electrical.

The petrol pump does not work: signs of breakage

Regardless of the design of the engine, if the petrol pump fails, the symptoms of its failure for both species are the same, and they manifest themselves as follows:

1. If the spark plugs are working, the spark is good, the engine is spinning, but there are no flashes in the cylinders.
2. Individual flashes occur in the engine cylinders, but the motor does not start.
3. The motor starts, but at the same time "swim" turns.
4. The engine starts, idle turns are normal, but if you try to increase them or start moving, the motor stalls.
5. During the movement, the machine twitches, when trying to raise the revolutions, the dips in the motor's operation are felt, the dynamics of the car are reduced (does not pull).

It is worth noting that similar symptoms can occur with other breakdowns, for example with a heavily soiled fine filter, faulty DMR (air flow sensor) or clogged injectors. Therefore, it is impossible to blame the fuel pump for any such symptoms.

In injector cars, when the ignition is switched on, a buzzing sound is heard from under the rear seat, this turns on the electric motor that pumping fuel, if there is no sound, then the gasoline pump does not work.

The mechanical gasoline pump refused: what are the reasons?

The reasons why the VAZ-2110 petrol pump does not work may be several:

• The most common failure is damage to the diaphragm, since it is she who pumps gasoline, which means that she does most of the work, so she is most prone to wear.
• Failure of fuel pump valves.
• Contamination of the internal strainer of the gasoline pump.
• Pump drive failure.

Electric fuel pump does not work, possible causes of breakage

In the injector engine, the fuel pump operates from the vehicle's on-board electrical system, so its failure is not always associated with the failure of the rocking mechanism itself. The cause of the fault may also be: a failed fuse, relay or oxidation, burning contacts on the wires that feed the electric motor.

Another common reason why the petrol pump VAZ-injector does not work, there may be a strainer installed at its inlet. Despite the fact that it is designed for the initial, rough cleaning of fuel, its grid has a fairly dense structure. And since the pump is in the tank, it practically touches its bottom and the precipitate accumulating there, which pollutes it.

Well, the worst thing is the failure of the motor responsible for the circulation of gasoline inside the pump or the failure of the elements of its design.

Methods for checking the fuel pump

To find out whether a mechanical gasoline pump works or not, it is very simple, by simply disconnecting the end of the hose connecting the pump to the carburetor, and, having lowered it into an empty bottle, press several times on the manual pumping lever on the pump. The gasoline should flow out of the hose with a pulsating jet. This will determine whether the internal components of the pump are working or not.

To understand why a gasoline pump does not work on an injector engine, you first need to "ring" its electrical circuit. It is better to start the test from the end point, that is, from the pump itself. A test lamp is connected to its terminals, and if it turns on with the turn of the key in the ignition switch, it means that everything is in order with the electrician, the breakdown should be searched in the pump itself, if not, then in the fuse, relay or in the wiring.

To check the gasoline pump itself, you need to find out what kind of pressure it creates in the fuel rail:

• At idle, its value should be in the range of 0.23-0.25 kPa.
• During the start-up of the motor - 0.3 kPa.
• When you press the accelerator - 0,28-0,3 kPa.
• When compressing the return tube, which returns excess gasoline to the tank, the pressure should rise to 0.4 kPa.

If in any of the modes the pressure does not correspond to the norm, therefore, the gasoline pump does not work as it should - its elements are badly worn and need repair or replacement.

Trouble-shooting

To fix a mechanical gasoline pump, you will need to purchase a repair kit, which includes a diaphragm and valves - these parts can be changed by yourself. Also it will not be difficult to replace the pusher with a spring. If the breakdown is more serious, then the point of resuscitation disappears, it will be cheaper and easier to put a new fuel pump.

The electric gasoline pump has a non-separable casing, and it's better not to try to repair it without having certain skills, it's better to entrust such work to specialists. The only thing you can do yourself is replace the grid of the internal coarse filter. But even here you need to know that grids are of different types, so you have to take out a filter from the tank to get a sample.

Prevention of damage to the gasoline pump

To extend the life of a gasoline pump, you need:

1. To monitor the quality of fuel, fueled in the car.
2. Completely rule out the possibility of water entering the tank.
3. During scheduled maintenance, it is essential to change the fuel filters.
4. In the event of a mechanical damage to the fuel tank, the petrol pump must be dismantled and its condition checked.
5. Periodically clean the fuel tank of possible accumulation of sediment, consisting of the smallest solid particles that are contained in gasoline.

The implementation of these simple rules will favorably affect not only the fuel system, but also the engine itself.