How to check a fuel pump: measuring pressure and troubleshooting it yourself


VAZ 2110 fuel pump injector, VAZ 2112 fuel pump, etc. — electric fuel pumps, installed on many VAZ models with an injector. The operation of this type of fuel pump is partially controlled by an electronic control system (ECM), which takes into account the air-to-fuel ratio, throttle position and exhaust composition.

The VAZ fuel pump (2110, 2112) is designed to supply fuel from the gas tank to the vehicle’s internal combustion engine. In this case, fuel from the car’s gas tank must be supplied uninterruptedly to the internal combustion engine, and under a certain pressure. This is the key to stability and reliability of the car’s power unit.

If the fuel supply is disrupted or stopped altogether, there is a high probability of failure of one of the devices in the overall fuel supply circuit. One of these elements is the VAZ 2110 (21102) fuel pump. Next, we will look at why the pump can fail, what its malfunctions are and how to fix them.

Causes: fuse, relay, connector

The pump power circuit includes many elements: closed relay contacts 5, fuse 3 (15 A), “+” wire, “pump-to-ground” wire. The most “difficult” defect is a short circuit of the “+” wire to ground. By the way, the cord itself is laid on metal, so such a defect cannot be ruled out.

Mounting block for dashboard

Both the relay and the fuse are located in a block located under the dashboard on the right. A fuse can blow in two cases:

  • The “+” cord makes contact with ground;
  • The motor resistance decreases due to overheating.

The first defect may be “floating”, and then it will be difficult to identify. But before calling an electrician, try checking everything else:

  • Relay 5 should click twice: when the ignition is turned on and after 1.5 s. If this does not happen, replace the relay;
  • Check fuse 3. If it is blown, you need to look for the cause.

Consider the situation: the relay is working, but the fuse is blown. Then we do this: disconnect the pump connector, install a new fuse and measure the voltage at the terminals. Details are below.

Connectors under the hatch, disconnecting them

You need to remove the hatch under the rear seat: two screws are unscrewed with a Phillips screwdriver. Next you need to disconnect the connector on the module, and then move on to the block under the dashboard.

First, turn off the fuel pump!

Replace the fuse. Let's move on to the fuel pump: connect the probe (zero cord) to any of the mounting studs. Voltage should appear on the “gray” wire when the ignition is turned on. And also check the potential difference between the “gray” and “black” wires - it should be equal to 12 volts, and also at the moment the ignition is turned on. Wiring:

  • The two outer cords are the FLS sensor;
  • “Black” – minus power supply;
  • "Grey" is a plus.

The "black wire" sometimes loses contact with ground. At the last step, we checked exactly this version.

There are reviews from owners that say: the fuel pump on a VAZ-2112 does not work if the electric motor is working properly and there is voltage in the connector. This happens when the contacts of the internal terminal block oxidize (see photo).

Internal connector - yellow

Getting to the connector on the motor is not easy - you need to remove the fuel pump module by unscrewing 8 nuts around the perimeter.

Diagnosing the fuel pump

Safety precautions

Before unscrewing the nuts, you need to disconnect the two hoses. But first try starting the engine. The power supply to the fuel pump is not connected.

Please note - the power is turned off here!

Everything is ready for dismantling if:

  • External connector is disabled;
  • It is impossible to start the engine, although the on-board network is not de-energized;
  • It is better if the tank is filled less than 50%!

You need to unscrew two fittings from the module cover (top photo). Then use a socket wrench to unscrew the nuts from the studs and remove the retaining ring.

There is very little left to the internal connector

Having gained access to the internal connector, you need to clean its contacts. Assembly is carried out in reverse order. Good luck!

Oxidation of the terminals of the internal connector is a typical disease of the VAZ-2112 fuel pump, and only one of the contacts does not work. The “+” terminal is more often oxidized.

Ground contact

Problems with the fuel pump weight can be indicated by incorrectly indicating fuel. Poorly secured ground can cause the fuel pump to stop pumping fuel. The ground wire is located under the dashboard and runs through the entire interior of the car. You need to find it, clean the contacts and secure it properly to the fuel pump.

Next to the ground, under the dashboard, there is
a fuel pump relay . After turning on the ignition, the operating relay allows the pump to create the required pressure in the system in a few seconds, after which it turns off. When you turn the key in the ignition, you can hear a soft click, which means that the fuel pump relay is turned on, and exactly the same when it is turned off.
If the relay does not make a click, then the problem is in it or in its contacts. Then it is advisable to replace it with a new one. When looking for the cause of a non-working fuel pump, you need to check the fuse. It is located under the hood and has a resistance of 15 A. It must be carefully inspected; if it is not working, it should be replaced with a new one. The fuel pump in the VAZ-2110 car is immersed in gasoline for active cooling, and the bad habit of driving a car with a minimum amount of gasoline in the tank can very soon cause the fuel pump motor to become inoperative due to burning.

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Advantages of injection models

The main function of the pump is to supply fuel to the combustion chamber. It must meet certain requirements. The main criterion is pressure.

The pumps for injection and carburetor engines are different. Thanks to the engine with direct fuel injection, there is no need for preliminary preparation of the combustible mixture. As you know, the carburetor is the weak link. Difficult adjustments, clogged jets, difficult starting in cold weather create inconvenience for owners of classic VAZ brands.

Tens and VAZ-2112 internal combustion engines have significant advantages. Let us note the advantages of injection units:

  • support for environmental standards;
  • direct injection into the combustion chamber;
  • fuel economy;
  • system reliability;
  • increased engine power;
  • starting a cold unit without warming up;
  • dispensing a portion of the mixture;
  • The fuel module is controlled electronically.

Unfortunately, the injector has a number of disadvantages. Maintenance and repairs have to be carried out at a service station. It also requires qualified personnel and a computer to determine the malfunction of electronic components. Let us point out other disadvantages:

  • design complexity;
  • high requirements for the octane number of gasoline;
  • complex diagnostics and repairs;
  • expensive spare parts and equipment.

How do fuel pump breakdowns manifest themselves?

We will not consider a broken relay or a blown fuse as a serious reason. Sometimes the relay itself is enough to be removed and inserted into place, and the system will work; the contacts are simply oxidized, and the fuse needs to be tested with a tester and, if necessary, replaced with a similar one.

A much less pleasant situation is when the coarse filter, which is located in the fuel module along with the pump, becomes clogged. The symptoms of a breakdown are floating, so it’s quite difficult to immediately understand what needs to be done. The first signs of a clogged coarse filter:

  • reduction in engine power;
  • lack of traction at high speeds;
  • Unstable engine operation at low and idle speeds;
  • Difficulty starting the engine.

Signs of a fuel pump malfunction

Using these signs, you can determine that the fuel pump is not pumping.

  1. The most common sign of a faulty fuel pump is that the car drives intermittently. While driving, the car begins to sharply slow down and then accelerate. Uniform movement of the vehicle is ensured by a continuous supply of fuel.
  2. The second most common symptom is floating engine speed at idle. This way you can determine if the fuel pump is faulty before you start driving.
  3. The engine starts with difficulty or does not start at all. Quite often this happens because the fuel pump has completely failed. The symptom is not the most common, since the reason that the engine does not start may lie in a variety of malfunctions.
  4. The car's dynamics deteriorate. When you press the gas pedal all the way to the floor, the car jerks or does not respond at all to moving the pedal. In this case, the fault may lie not in the pedal, but in the fuel pump.

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Do not forget that all the signs listed above are not one hundred percent. Such malfunctions can be caused by failure of various other engine parts. The engine speed may well fluctuate due to a malfunction of the mass air flow sensor or throttle position sensor.

Such malfunctions most often occur due to low quality fuel or uncleaned injectors.

Purpose and principle of operation of the fuel pump

The fuel pump is designed to pump fuel from one point to another. In a car, the role of the first point is played by a fuel reservoir - the tank, and the second - by the engine, where the pumping takes place. This process occurs at a certain pressure, which is maintained by the pump reducer, which is a very important point.

Fuel pump diagram

Fuel pumps are divided into 2 types according to the type of drive: electric and mechanical. Inside the first there is an electric motor with a mini-pump, which operates from the mains and uninterruptedly pumps fuel into the engine. The second type is becoming increasingly rare, as it is installed on carburetor cars, and operates due to the reciprocating movement of the lever.

Fuel pump diagram

Causes of malfunctioning fuel pump

Fuel pumps are different. It all depends on the specific brand of car and the characteristics of the pump itself.

Knowing the causes of problems in the vehicle’s fuel system is a necessary condition for its successful repair. Problems may arise for the following reasons:

  1. Wiring problems: Wires have become dirty, rusted, or melted. As a result, the electric voltage decreases and fuel pumping becomes more difficult.
  2. Debris and dust getting into the gas tank. Rust in the tank. As a result, the fuel becomes unclean and causes problems. Poor quality fuel also pollutes the gas tank.
  3. Filter dirty. Fuel pressure decreases and the functions of the device are weakened.
  4. Driving with an empty tank. This leads to a decrease in pressure and overheating. It dries out and becomes damaged.

To effectively treat a living organism, it is important to know not only the symptoms, but also the causes of the disease. It’s the same with the operation of car systems: you need to find out the causes of problems in the operation of the fuel pump

The gasoline pump is one of the key elements of the automobile fuel complex. It is responsible for transferring fuel under pressure to the injectors (when the car uses a system in which fuel is injected) or to the carburetor. Like other parts of the car, the pump may stop working properly.

The device can be mechanical or electrical. It all depends on its functional characteristics and structure.

How to check functionality

This is easy to do at home. First you need to remove the pump and place it in a vice. Then connect a hose to each branch pipe. One hose must be directed into an empty container, and the other into a container with gasoline. The mechanism must be pumped by hand. If the fuel moves from hose to hose, then you can be happy. This means everything is fine. If this does not happen, then most likely the part needs to be replaced.

Knowledge of the operation of all vehicle systems and experience in troubleshooting them will help save money and provide invaluable assistance in the event of a breakdown far from populated areas.

Electric motor

If searching for a problem in the fuel rail and wiring does not produce results, you need to check the fuel pump motor. It is responsible for circulating fluid in the internal part of the fuel pump. When checking, it is necessary to take into account that after a certain period of time the terminals on the fuel pump may oxidize and there will be no power. This is also often the reason why the fuel pump stops working. This means that the motor is most likely working, but the terminals need to be cleaned and tightened.

How to check and replace the fuel pump relay

If the electric fuel pump does not show signs of life when the ignition is turned on, this does not mean that it has burned out. The cause of the breakdown may also be the “relay”. The simplest method of checking the fuel pump relay is by ear - it should click when the ignition is turned on. If you don’t hear a click, then most likely the relay is faulty.

However, everything is not so simple - the breakdown can be “tricky”, for example, the car does not start the first time. The cause of the breakdown may be burnt relay contacts.

In this case, checking the functionality of the pump is very simple:

  1. Remove the protective cover that hides the fuse and relay block.
  2. Unscrew the fastenings of the block and remove it; it will remain attached to the wires.

  3. Pull the relay out of the block and place a jumper between 2 opposite contacts, so we will supply power directly to the fuel pump.

  4. If the electric motor of the fuel pump begins to make noise with this connection, it means that most likely the fuel pump itself is working, and the fault lies in the relay. In this case, replace the relay.

Wiring

On almost all car models, the wiring to the fuel pump consists of three wires: “positive”, “negative” and a wire for determining the amount of fuel in the tank.
If the fuel pump stops pumping, the wiring may be damaged. You can check the power using a 12 W lamp, powering it from the external connector of the fuel pump. When the ignition is turned on, the light should light up. If not, then the external circuit is broken somewhere. To check the external wiring, you need to connect in turn the “positive” and “negative” contacts removed from the fuel pump power connector. It is necessary to close the “negative” contact to ground, after which the light will light up when the ignition is turned on. So, it can be determined that the contact is inoperative. If the lamp does not light up, then the “positive” contact is damaged. Placing a contact on the relay in which the light does not light up, there may be a problem with the wiring in the section from the relay to the fuel pump.

When should you check your fuel pump?

It is necessary to check all potentially faulty components one by one, and the fuel pump first.

Problems when starting and running the engine are not always associated with the fuel pump. Sometimes the signs of a fuel pump breakdown are the same as those of a faulty fuel pressure regulator , injectors or jets, spark plugs and high-voltage wiring. Even experienced specialists who know by heart all the signs of a “dying” pump cannot unambiguously determine the type and cause of the breakdown the first time, and it is necessary to check all potentially faulty components one by one. In this case, the fuel pump is usually checked first. In this case, there are two types of malfunction - the fuel pump does not work at all or does not produce the required pressure. In the first case, the malfunction can be recognized by ear, since it should start when the ignition is turned on. In the second case, you need to know how to check the pressure of the fuel pump. Here you need to use a special pressure gauge. We list the main symptoms of a fuel pump malfunction:

  • the engine does not start;
  • the engine is unstable;
  • the engine lacks traction during sharp acceleration;
  • The engine lacks traction at low speeds.

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Diagnostic device

To determine the pressure in the main line, a device is needed. It's easy to do it yourself. You need to take a 10 atmosphere pressure gauge, a fitting and an oxygen hose with an internal diameter of 9 mm. We twist all the elements and tighten them with clamps.

The meter is connected to the ramp. To do this, remove the plastic cap from the end of the tube. Next, use a tire cap to unscrew the nipple.

Bleed off excess gasoline. Before draining the flammable liquid, place a rag to prevent gasoline from getting on the generator. Smoking and using electrified tools near the hood is strictly prohibited.

The free end of the hose is pulled onto the ramp. Secure the clamp. After connecting the battery, turn on the ignition. They take readings. The pressure of the VAZ-2110 fuel pump injector will deflect the pressure gauge needle to 3 atm.

After starting the engine, observe the movement of the needle. On working equipment, the pressure will be maintained within 2.8-3.2 units. If no deviations are found, then the VAZ-2110 fuel pump, injector and regulator are working correctly. It is advisable to remember the characteristics of the equipment.

The pump capacity is about 2 liters per second. If problems arise with the fuel supply, the pump must be replaced. Before checking the pump, make sure that the remaining elements are in good working order. The filter or mesh may be clogged. The fuel filter is changed and the mesh is cleaned.

If everything has been checked, but the fuel pump does not work - article numbers

In general, the pump article number for VAZ-2112 engines looks like this: 21102-1139009-XX. Instead of the letters XX there are numbers, for example 02 or 03. They indicate the manufacturer. So, modules from different factories are not interchangeable! The resistance of the FLS resistor is different in them. However, when replacing the FLS sensor, you can borrow it from the “old” module. That's what they usually do.

Until April 2002, article numbers of the type 2112-1139009 were used.

Almost every module available for purchase contains a built-in pressure regulator. There are also exceptions - KSZC-A243, for example. The meaning is as follows:

  • All internal combustion engines with a volume of 1.5 liters are equipped with a ramp with an “external” regulator (2112-1160010);
  • The 21124 or 21114 motor requires a built-in regulator.

In conjunction with 1.5 liter engines, you can use any module – both with and without a built-in regulator.

Designations of analogues

  • 21102-062213.0XX – instead of the letters XX there will be a plant designation (07, 13, etc.);
  • KSZC-A233 or A243 – KSZC brand. No pressure regulator .

Master node of the system

The VAZ-2110 fuel pump is equipped with an electric drive. Its body is lowered into the fuel tank. Gasoline is both a pumpable fuel and a coolant. It should be remembered that traveling with an empty tank is fraught with overheating of the VAZ-2110 injector fuel pump.

This electrical device is an independent unit. Accordingly, its operation does not depend on the state of other mechanisms. A necessary condition for rotating the VAZ-2110 fuel pump rotor is maintaining normal voltage on the on-board network.

The voltage comes through the ignition switch. When the key is moved to position 1, the circuit is closed to turn on the drive. The VAZ fuel pump fills the fuel rail. The engine is ready to start.

If symptoms of poor fuel system performance occur, the pump should be checked. We list the signs that make it possible to replace the VAZ-2110 fuel pump:

  • the car is malfunctioning;
  • accelerates poorly;
  • twitches while driving;
  • won't start at all
  • gasoline does not flow to the ramp.

First of all, a hearing test is performed. After turning the ignition key to position No. 1, there should be a noise under the rear seat. The sound lasts for a couple of seconds. This means that the pump has pumped up the required pressure.

What kind of fuel pumps are installed on VAZ 2110/2112 cars

The fuel pump is considered the most important element of the fuel system of any car. So, depending on what type of engine the VAZ 2110/2112 model is equipped with, the choice of fuel pump will also depend. An electric pump is installed on injection cars, and a mechanical one on carburetor cars.

The family is equipped with fuel pumps produced by AvtoVAZ. However, these units do not have a high service life and reliability, so often car owners do not wait until the fuel pump fails and replace it.


Installed at the factory on every VAZ 2110/2112 model

Most often, fuel pumps (Russia) and “Bosch” (Germany) are chosen for replacement. Their quality and durability have been known for a long time, although their cost is several times higher than the price of AvtoVAZ gasoline pumps.


The German manufacturer ensures the quality and durability of the products

It’s worth mentioning separately about the location of the fuel pump in the VAZ 2110/2112: the device is not located under the hood. To achieve maximum optimization of the fuel pump, manufacturers install it directly into the fuel tank. That is, to get to the pump, you will need to fold back the cushion in the back seat of the car and open the hatch hidden under the carpet.


The fuel tank and fuel pump are located under the seat cushion.

Features of the injection power system

The tasks of fuel pumps in carburetor and injection engines are somewhat different. If for a carburetor engine it is important to simply supply gasoline to the carburetor, then for an injection system this is not enough. The fuel pump must not only pump fuel from the tank to the ramp, but also create a certain pressure, without which the engine simply will not start.

Access to the fuel pump in injection cars is also complicated by the fact that in cars of recent years of production it is mounted together with a fuel receiver and a coarse filter directly in the gas tank. This complicates the diagnosis, repair and maintenance of the entire fuel module, but simplifies the design of the pump, since the gasoline itself lubricates and cools it. But this is precisely what often leads to unit breakdowns.

Product selection

AvtoVAZ offers an original fuel pump for 4,000 rubles. The original catalog number is 2112-1139009 . But many car enthusiasts buy and install cheaper analogues instead of the original.

Analogs


Bosch fuel pump.
A non-original part is often no different in quality from the original. So, if the vehicle owner wants to save money, then you can install a non-original part. Let's consider the main offers of analogue companies:

  1. Fenox EFM33006O7 - the cost of such a part will be about 3,000 rubles.
  2. Bosch 0 560 454 035 - as they say, I took BOSCH, and ... (go ahead).
  3. Ween 192-0262 – the price on the spare parts market will be approximately 3,000 rubles.
  4. Pekar 2112-1139009 - will cost a little more than the previous two, the average price is 3,500 rubles.
  5. ATS 53453 - they praise, but the price tag is good. We know they put one like this as a replacement for expensive originals on Peugeot.


    ATS fuel pump.

How to check the operation of the fuel pump?

First, you should check the fuse. To do this, check the instructions for its location. Next, you should check the voltage at the pump. Before doing this, be sure to check if everything is in order with the battery. The voltage at the fuel pump terminal must be checked using a multimeter or tester. The instruction manual always indicates the required voltage.

Using a tester, check the voltage supply to the fuse. Often this is where the electrical circuit breaks.

If the search does not yield results, then the voltage should be checked on the contacts themselves. All contacts must be in place and connected to ground. A broken contact or its oxidation leads to failure of the fuel pump system. If no broken contacts are detected, but the voltage drops by more than 1 volt, then the problem is in the wiring or oxidation of the contacts. There should be no short circuit in the wiring.

If, after checking the voltage, contacts and fuse, you do not find any problems, then the problem lies in the fuel pump itself. In this case, the fuel pump will most likely require replacement. In practice, it most often turns out that replacement is a last resort. First, you should try to restore and test the fuel pump again.

Before you check the fuel pump, you need to remember that, as mentioned above, pressure is the most important characteristic of the fuel pump, so it is worth measuring its level.

How to check the pressure in the fuel rail?

You will need a pressure gauge that measures pressure in the range from 7 to 10 atmospheres. If you choose a pressure gauge with a large margin, you risk getting less accurate measurement results. Specialized stores sell a kit for measuring pressure, but you can also design your own device.

If you want to assemble the device yourself, you will also need a hose with an internal diameter of 9 millimeters. You will also need plumbing tow, with which you can seal the connection between the pressure gauge and the tube. All parts are connected and tightened using a clamp. You will also need a car spool. Next you need to perform a series of actions:

  1. Place the car on a level surface that is prevented from rolling, turn off the ignition and open the hood.
  2. Check that the injection nozzles have access to the fuel rail.
  3. Find the fuel pressure plug and remove it. Then you should unscrew the nipple using the spool.
  4. Prepare an empty container (a regular bucket will do) and a clean rag. This is necessary to collect residual fuel, which under pressure can splash out in different directions. Therefore, take care of the safety of your skin (especially your face and eyes).
  5. Connect the device to the fitting and begin checking the mechanism.

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Checking the pressure in the fuel rail should occur in four operating modes of the power unit:

  • when the ignition is on;
  • at idle engine speed;
  • code the fuel pressure regulator tube is reset;
  • when the drain tube is compressed.

Fuel rail pressure measurement results

The results may vary slightly for different car models, but in general they should be as follows:

  • when the ignition is turned on, the pressure must be at least 3 atmospheres,
  • at idle engine speed - at least 2.5 atmospheres,
  • when the pressure regulator tube is reset - at least 3.3 atmospheres,
  • when squeezing the drain tube - at least 7 atmospheres.

Fuel rail pressure fluctuates slightly during preparation. When you press the pedal, it suddenly takes on a value of 3 atmospheres; when you release the pedal, it drops to 2.5 atmospheres. When fuel enters the fuel system, turn off the ignition and begin observing the pressure gauge. The pressure in this case should drop to 0.7 bar and remain unchanged.

If the pressure drops to zero, there may be a problem with the fuel pressure regulator. In this case, the regulator must be replaced immediately. The cause could also be the fuel pump check valve.

It is necessary to observe the behavior of the pressure gauge even at 3,000 engine speeds. A drop in pressure will indicate a faulty fuel pump. Sometimes the fuel pump cannot reach the required pressure for a long time. In this case, the problem lies in a clogged fuel filter, which needs to be replaced, or in a dirty fuel pump mesh (read more about where the fuel filter is located).

If the above methods do not reveal a malfunction of the fuel pump, you will have to diagnose other units (DPZD, IAC, mass air flow sensor, compression in the engine and some other indicators and parts).

Replacing the fuel pump on a VAZ 2110/2112 with your own hands

If the car owner has accurately diagnosed the failure of the pump mechanism in the fuel system, it will need to be replaced. It is worth noting that replacing the fuel pump on VAZ 2110/2112 cars is quite simple; even an inexperienced driver can cope with this task.

The fuel pump is usually replaced not only because it has lost its functionality, but also in other cases:

incorrect pressure readings when the pump is working;

insufficient fuel capacity;

after purchasing a new VAZ in order to get rid of the “weak points” of the model.

To work you will need a small set of tools:

10mm socket wrench.

The work procedure can be divided into two stages: dismantling the old device and installing a new one.

Instructions for dismantling the fuel pump

Disconnect the “+” terminal from the battery.

Fold back the seat in the back row and remove it.

Find a small hatch under the carpet.

Unscrew its fastenings and remove the cover.

Remove the connector with wires from the fuel pump.

To make it more convenient to work, the plastic clamps on the fuel pipes are cut, the tubes themselves are separated and removed from the fuel pump.

The pump itself is attached to the tank with 8 bolts. Using a 10mm wrench, you need to unscrew all the bolts and pull the device out of the socket.

The pump is pulled out along with the float and seal.

The procedure for removing a faulty fuel pump will take no more than 10 minutes - everything will depend on how rusty the fastening bolts are.

Installation instructions for fuel pump

A new pump is inserted into the vacated socket. In this case, the arrow on the body should point towards the rear of the car - this is the only way to ensure the correct position of the device.

After which the pump is screwed back to the tank with the same eight bolts.

Next you will need to connect the two fuel pipes to each other.

A connector is connected to the pump contact.

The final stage is installing the hatch cover and returning the rear seat cushion to its original place.

The procedure will take no more than 7–8 minutes.

Video: how to replace the fuel pump on a VAZ 2110/2112 with your own hands

Thus, the owner of cars of the “tenth” VAZ family can independently cope with such work as checking and replacing the fuel pump. It must be said that the fuel pump is indeed considered one of the most vulnerable points on the VAZ 2110/2112, so owners better be prepared in advance to carry out the necessary procedures with this device.

Possible causes of fuel pump malfunction

Mechanical fuel pump disassembled

A mechanical fuel pump may fail for the following reasons:

  1. If the integrity of the diaphragm is damaged.
  2. After dirt accumulates under the valves.
  3. When the filter is clogged.
  4. When the spring loses its elasticity.
  5. If the seal of the housing is broken.
  6. Due to natural wear and tear of parts during operation.

The electric fuel pump of a modern car is quite reliable. Malfunctions in it arise only due to the influence of certain factors, among which the most common are the following:

Burnt contacts inside the fuel pump

1. Faulty wiring in the form of dirty, rusty, melted or damaged wires in the fuel complex interferes with the operation of the device and also limits the required current parameters, making it difficult to pump fuel.

2. Debris and foreign impurities in the fuel tank in the form of rust, dirt, water, mechanical particles that penetrate the fuel pump and cause its breakdown.

Clogged fuel pump filter

3. A clogged fuel filter with debris from the tank contributes to a sharp decrease in the pressure created by the pump and a deterioration in its operating parameters.

Melted fuel pump turbine

4. Driving a car for a long time with a small amount of fuel, during which the pump is not immersed, experiences significant overheating, quickly consumes internal lubricant and fails.

5. Natural wear of the rubbing parts of the pump.

Method number 1. Hatch with a lock

For many cars, you can separately buy a gas filler cap that matches the size and diameter. After installation, the cover is securely fixed and can only be opened with a separate key or, in rarer cases, with a combination lock. This way, not only will thieves not be able to drain the fuel from your car, they won’t even be able to open the gas tank. Such devices cost, especially for the domestic auto industry, literally a couple of hundred rubles. But just imagine how much money you can lose when a full tank that you just filled up ends up in someone else's gas can under the cover of darkness.

Problems with the operation of the vacuum type device

The vacuum pump may malfunction. This can happen for several reasons:

ProblemsCausesSolution
Insufficient vacuumInsufficient oil levelAdd oil to the required level
The oil has become dirtyDirty engine. The higher the alkali content in the oil, the faster the engine cleans and the oil turns black. Replace the oil with clean oil. If the alkali content is high, replacement is required after 5,000 kilometers.
The oil fill hole is cloggedSmall particles on the surface of the lidClean the inlet and rinse the filter
The integrity of the hoses is compromisedWear, mechanical damage, hose connection failureCheck hoses and their connections
Insufficient pump powerLoss of voltage from the generator to the pump due to unsuccessful implementation of standard wiring, insufficient device sizeReplace the wiring or purchase a new part of the required power
Oil started leakingThe integrity of the oil container is damagedReplace container
The cover of the hole for draining the oil does not fit well or the rubber ring has become unusableThe thread of the cover is torn off, the ring is worn outReplace the cover and replace the gasket
Oil splashesPermissible oil level exceededDrain some of the oil to the desired level
The pressure at the air evacuation fitting has been exceededInsufficient pump powerInstall a more powerful pump
The pump is hard to startThe temperature has become too lowThe device must be turned on and off several times in a row or the oil must be heated
Breakdowns in the electrical part of the pumpVoltage surges, short circuitCheck and eliminate breakdowns
Garbage has accumulated insideDirt in the gas tankExamine the contents and remove the blockage, clean the gas tank
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