Gazelle Sable. Fuel pump malfunction (does not pump gasoline)

Tips for motorists

In the operation of the submersible electric fuel pump on a Gazelle car, the following take part: the main relay, the fuel pump relay, the electronic control unit, and fuses protect this electrical circuit. In addition, if the car has an anti-theft system installed, then another relay will be added to the circuit, which will cut off the voltage supply to the fuel pump terminals.

And those Gazelle cars that run on gas will still start on gasoline and in their electrical circuit of the fuel pump, an additional relay will also be installed that will turn off the operation of the fuel pump at the moment the engine switches to gas.

Therefore, when troubleshooting problems associated with a non-working gas pump on a Gazelle, you need to start by checking the integrity of the fuses . You also need to check the condition of the contacts for oxidation. Next, we check the operation of all relays that are used on this vehicle in the electrical circuit for supplying voltage to the fuel pump terminals. If this does not help, then you will have to check the wiring and connections from the electronic control unit to the main relay and the fuel pump relay.

Another common cause of fuel pump failure is oxidation or burning of the negative contact located on the fuel pump inside the tank. There is a white block there, but please do not confuse it with the block that is located on the surface of the gas tank. Typically, this malfunction initially manifests itself by periodically turning the fuel pump on and off. If this problem occurs, then these contacts will have to be periodically cleaned by removing the module or connected directly once and for all, bypassing the terminal.

Unfortunately, the driver is not always able to independently find faults associated with the failure of the submersible fuel pump on a Gazelle car and has to look for a competent auto electrician to solve this problem.

If the starter of your car turns normally, but the car does not start, the first thing you need to do is check that the fuel pump is turned on. On domestic cars, its operation can be heard from the passenger compartment; when the ignition is turned on, a characteristic buzzing sound comes from under the rear seat or trunk. If the fuel pump does not work, you need to check the integrity of the fuses and the activation of the main relay of the engine management system and the fuel pump relay. On the VAZ-2107, VAZ-2108, VAZ-2109 and their modifications, relays and fuses are located on the shelf under the glove compartment or under it. On VAZ-2110 and similar ones, you should look in the heater console on the passenger side by unscrewing the fastening screws and removing the side cover. On GAZ cars they are located under the hood on the front wall of the cabin, closer to the passenger side.

General scheme

Modern engines are largely focused on economical operation with reference to environmental requirements.

Therefore, they differ:

1. A large number of various sensors;
2. Increased length of wires;
3. Electronic control units for subsystems and the entire power unit;
4. On-board diagnostic module (computer).

Poster from the service manual for a GAZelle with a ZMZ-40522 engine

Accordingly, the wiring diagram for the Gazelle 405 has its own characteristics, most of which relate to ensuring the correct operation of the injection system, often called the injector.

This is where, according to many diagnosticians and auto electricians, lies the weak link that affects the car engine. And one such feature will be discussed in this publication.

Electronics help

On cars with EURO 3 engines, the wiring diagram for the 405 Gazelle provides a diagnostic module.

Its frequently encountered names among motorists:

• on-board computer,
• trip computer;
• multitronics (by manufacturer's name), etc.

In addition to its basic information functions, the on-board computer is also able to inform the driver:

• Stepper motor position.
• Engine speed.
• Injection controller error codes.
• Mass air flow.
• Throttle position.
• Onboard voltage value.

Note. If a malfunction occurs in the operation of the power unit, the route PC will report errors. From their decoding, you can guess which electrical wiring diagram for the Gazelle 405 is subject to close monitoring. But he, of course, “will not say” about the true reason, but will only point out the probable reason that caused the unstable operation of a particular node.

Vehicle weight

Let's look at an example when a car stops obeying the gas pedal . The car refuses to move, when starting it keeps the speed at 2000 rpm and does not allow movement.

Read more: How to unlock the engine from a Pandora alarm

The trip computer often reports in such situations that there are errors:

1. With throttle;
2. With crankshaft sensor;
3. With air flow sensor.

The example shown in the video below shows unstable operation of the power unit.

The factory instructions prescribe diagnostics using special equipment, as a result of which the owner, using a brute force method, excludes one or another node from the “suspect list”.

In fact, the reason for the failure is tritely simple - a break in the throttle ground wire , which, being screwed to the exhaust manifold stud, is subject to vibration and simply falls off (this kind of trouble happens not only with GAZ products - see the article original wiring diagram for VAZ 2112).

Please note: For better contact with the vehicle ground, the throttle electronics are powered by a separate wire - in the photo below.

The fuel pump relay does not turn on.

If the fuel pump does not work, then first of all you need to check the attraction of the main relay and the fuel pump relay. If the main relay does not click, then it is necessary to check its switching circuit and its serviceability. How to do this is described in the article the main relay does not turn on,

In the case when the main relay turns on, but the fuel pump relay does not, it is necessary to check the power at pins 85 and 86. When using a test lamp, its current consumption should not exceed 0.25A, otherwise damage to the controller may occur. If the control lamp does not light up on any terminal, then the relay is not receiving power. This may be caused by a blown fuse or a broken power cord.

In the case when the lamp burns brightly on one terminal, and at half-glow on the second, and the relay may be activated, you should remove the relay from the socket and connect terminals 85 and 86 with a test lamp. When the ignition is turned on, the control lamp should light up and go out after approximately 20 - 30 seconds. If the lamp lights up and there is poor contact in the connection between the block and the fuel pump relay. If the lamp does not light up, there may be a break in the wire connecting the relay to the controller or the controller itself may be faulty.

The fuel pump does not work, the relay turns on.

Checking relay power.

In the case when the fuel pump relay turns on when the ignition is turned on, but the pump itself does not work, you need to check the power at terminal 87 of the fuel pump relay. To do this, touch terminal 87 of the relay socket with the output of the control lamp connected to the vehicle ground, and the lamp should light up. If the lamp does not light, it means the fuse has blown or there is a break in the wire.

If there is power at terminal 87, you should remove the relay from the socket, and instead place a jumper between pins 87 and 30. In this case, if the pump and connecting wires are working properly, the pump should start working and if this happens, the relay should be changed. If the pump does not start working, then, without removing the jumper, you need to touch the power wire on the fuel pump with a test lamp connected to the vehicle ground.

Checking the fuel pump power circuit.

If a submersible pump is installed on the car as part of the fuel module, you need to remove the connecting connector and touch one of the thick wires. When you touch one of them, the indicator lamp should light up. If the lamp does not light up on any of the wires, then it is necessary to eliminate the break in the wire from the fuel pump relay to the module connector or the pump itself, if the pump is of a remote type. One of the reasons for the break may be the anti-theft blocking of an installed non-standard alarm system.

In the case when the test lamp lights up on one of the thick wires of the connector or one of the terminals of the remote pump, you need to connect these terminals with a test lamp to each other. In this case, the control lamp should light up. If the lamp does not light, it is necessary to eliminate a break or poor contact in the wire connecting the pump to the vehicle ground.

If, when checking the wires and relay for turning on the fuel pump, no malfunction is detected, the electric motor of the fuel pump or its connection to the module connector is faulty. It is not difficult to find the cause by removing the fuel pump module from the tank. If there is poor contact with the connector, melting of the plugs will be visible. If melting is not noticed, then to check the pump itself, you can connect it to the battery. It should be taken into account that operating a submersible pump without liquid will damage the pump. A faulty pump should be replaced.

One of the most important elements of the fuel injection system of a gasoline engine is the electric fuel pump, which is located in the fuel tank of the car. The fuel pump pumps fuel into the system from the gas tank, creating a certain pressure.

Auto repair experts identify the following common fuel system problems that are related to the fuel pump:

• The fuel pump pumps poorly and does not create the required pressure;
• the fuel pump does not pump when the ignition is turned on;

Considering that the fuel pump is an electromechanical device, the most common fuel pump malfunctions are related to both the mechanical and electrical parts. Next, we will look at what signs indicate a breakdown of the fuel pump and why the fuel pump stops pumping partially or completely.

Read in this article

We fix it ourselves

As a rule, the price of diagnostics and work by a service station technician or electrician is quite expensive. Therefore, it makes sense to check the GAZelle wiring yourself . Very often, the cause of such sudden failures is loss of contact with the vehicle's ground. Moreover, such a problem occurs in many domestic cars - the same wiring Moskvich 2141, for example.

This wire should always be kept under control. Source

When detected, such a malfunction can be repaired quite easily:

1. Cut the fallen wire 5-7 centimeters below the oxidized contact;
2. Clean up;
3. Screw on the new contact;
4. Isolate;
5. Screw it to the stud, having previously cleaned the contact area with a small file.

Advice: if you have to replace the wiring yourself, then do not be too lazy when removing the old harnesses to mark on the new wiring the nodes and contacts to which it will be connected. To do this, you will need tape and paper with a pen - sign and stick handmade clues to the wiring (this advice will also help when using parts from other cars - see the article GAZelle 406 wiring diagram).

The fuel pump does not pump: causes and diagnostics

Let's start with the fact that if the gas tank is full, the battery is charged, the spark plugs are dry and there is a spark, the starter turns the engine normally, but the engine does not seize, then you should pay attention to the gas pump. A common problem is that there is no power to the fuel pump after the ignition is turned on. In a similar way, the malfunction manifests itself in motion, when the power to the fuel pump is lost and the engine suddenly stalls.

An equally important point is how much the fuel pump pumps. In other words, the pump may hum and buzz (power is being supplied), but not create the required pressure in the fuel line. The pressure in the fuel system with a working fuel pump must be more than 3 bar (which depends on the specific car model). The indicated pressure is accumulated in the fuel rail and has an indicator of 300 kPa and above.

To check, you need to measure the pressure in the fuel rail with a pressure gauge, taking into account the indicators that are the norm for a specific car model. Using the example of injection VAZs, the pressure when the ignition is turned on is 3 atmospheres, at idle the figure is 2.5 atmospheres, when you press the gas 2.5-3 atmospheres. This method will help you accurately determine:

• malfunction of the fuel pressure regulator in the rail;
• breakdown of the fuel pump or a noticeable decrease in its performance due to wear;
• severe contamination of filters (fuel filter and/or fuel pump mesh);

In the second case, when you press the gas, the pressure does not increase; in the latter case, the pressure gauge needle rises, but very slowly or jerkily.

A decrease in pressure below the norm will lead to the fact that the engine may not start or start with difficulty, stall, jerk, operate unstably and with failures. If this happens due to the fault of the pump and not the fuel filter, then there is a high probability that the coarse filter screen of the fuel pump is clogged. In this case, there is no need to change the fuel pump itself, since it will be enough to replace or even clean the mesh.

If you suspect that there is no voltage to the fuel pump, there is a quick way to check. It is enough to turn the ignition key and listen, as when you turn the key you should hear a slight hum from the fuel pump. If such a buzzing noise is not heard, it means there is no power to the fuel pump, there are problems with the wiring, etc.

Also in the general list of possible reasons why the fuel pump does not pump, the following are noted:

• failure of the fuel pump fuse;
• fuel pump relay failure;
• problems with the ground of the fuel pump;
• malfunction of the electric motor of the fuel pump;
• oxidation or damage to fuel pump contacts and terminals;
• the fuel pump itself is faulty;

Wiring to the fuel pump

On most cars, the wiring to the fuel pump consists of three wires: “plus”, “minus”, and also a wire for indicating the amount of fuel in the gas tank. If the fuel pump does not pump, then the cause may be a lack of power.

To check the power to the fuel pump, just take a 12-volt light bulb and supply it with power from the external connector of the fuel pump. After turning the ignition, the control lamp should light up. If this does not happen, then the problem is in the external circuits. If the lamp comes on, it will indicate the need to check the internal contacts of the fuel pump.

To check the external wiring, you should alternately connect the positive and negative contacts, which are removed from the fuel pump power connector, to the ground of the pump. The contacts must also be connected to the fuel pump relay. If you place the negative contact on ground, after which the ignition is turned on and the light comes on, then this means that this contact is faulty. If the light bulb does not light up, then problems with the “plus” are obvious. If you place a contact on the relay and the light comes on, there is probably damage to the wire on the section that connects the relay and the fuel pump itself.

Other causes of fuel pump malfunctions

Quite often, unprofessional installation of additional electrical equipment or security anti-theft systems leads to the fact that the power to the fuel pump is lost due to mixed up contacts or other connection errors.

Finally, let’s add that the gas pump in the gas tank is immersed in gasoline, in which it is actively cooled. The habit of driving with an empty tank can quickly damage the electric motor of the fuel pump, as it burns out.

What functions does the fuel pump relay perform, signs of breakdown. Where is the fuel pump relay installed, how to properly check the fuel pump relay.

Why does the starter turn normally, but the engine does not catch and does not start? Main causes of malfunction, checking fuel supply and ignition systems. Adviсe.

Diagnose faults that may indicate problems with the fuel pump. Self-check of the device, measuring the pressure in the fuel rail.

The causes of whistling and increased noise during operation of the fuel pump are overheating of the pump. How to diagnose and fix the problem yourself. Tips and tricks.

What to do if the car accelerates worse, does not pick up speed, or has failures during acceleration. Why the engine does not pull, how to find the reason for the decrease in power.

How to change a fuel pump. Location of the fuel pump, releasing pressure in the system, unscrewing the fuel lines, removing the pump, reassembling.

Checking the fuel pump of a carburetor car (mechanical)

Mechanical fuel pump - diagram

To check the operation of the fuel pump, you should:

1. Remove the fuel hose from the carburetor inlet fitting.
2. Immerse the hose in a specially prepared transparent bottle. By actively using the pumping lever manually, we notice how strong and dense the fuel is supplied. Air impurities should not be visually noticeable.

Delayed jet output is not a sign of a breakdown, especially if the car has been parked for a long time. As a rule, diaphragms eight and nine are the main cause of malfunction.

Be that as it may, you need to inspect both the strainer and the inlet/outlet valve.

Even if the gaskets are replaced, fuel may leak. In this case, the problem lies in the tightness of the fuel pump housing due to deformation during repairs.

Let's summarize:

The causes of fuel pump problems, both electrical and mechanical, are varied, and the need to find/fix a breakdown may take you by surprise along the way. By following the above recommendations, you will be able to independently carry out the entire necessary set of measures to diagnose this device. And you should start with the power supply (if it is an electric fuel pump) and the operation of the diaphragm when checking a mechanical fuel pump. Very often, the unstable operation of a fuel pump is not due to its breakdown, but to related parts - a filter, check valve or injectors.

Zavolzhsky Motor Plant (ZMZ) is one of the first domestic manufacturers of automobile engines to begin producing engines with an injection power system. One such high-quality engine can be called the ZMZ 405 - an engine from a family of four-cylinder engines that have been produced for almost 15 years. For the first time, this particular engine hit the market back in 2000, installed on the GAZ-3111 car. The plant itself positions the engine as an engine for small trucks and minibuses. It is installed on them - various cars of the GAZelle and Sobol injector line have this engine.

Over the past time, the ZMZ 405 has established itself as an excellent, unpretentious engine, ready for even the greatest difficulties on the road. The 405 motor is capable of withstanding heavy loads and this will not affect its service life. Also, the design of the motor is based on the unprecedented simplicity of the device - this engine, installed on any car, can be repaired and maintained by anyone in an ordinary garage with minimal knowledge, everything is done according to the included book and does not raise any questions. The same applies to fuel system repairs. In particular, the engine fuel pump injector is very easy to repair yourself.