The electric petrol pump on cars with an injector is the submersible fuel pump, which is installed directly in the gas tank. Structurally, such a pump is an electromechanical device, which takes fuel from the tank and feeds it to the engine. The task (BT) The fuel pump is injecting fuel into the fuel line. The result is the required pressure in the fuel rail for further injection of gasoline injector nozzles.
We also recommend reading the article about it, how to check the pressure of the fuel pump yourself. In this article you will learn how to measure the fuel pressure in the fuel rail (rails) using a pressure gauge with your hands.
In the list of typical problems it is necessary to allocate the following separately:
- buzz / whistle the fuel pump;
- the gas pump is hot;
- the fuel pump does not switch off;
Next we will consider the main reasons, which cause these problems, as well as consider available ways to test the fuel pump with your own hands.
The fuel pump whistles and hums
Let's start with that, that the quality of its operation of the fuel supply pump involves some noise or quiet humming after turning the ignition key. In other words, the fuel pump hums at that time, while creating working pressure in the highway. This process continues 2-3 sec, after which the driver may hear a light click. This click gives the relay of the fuel pump.
Note, that many car drivers with mileage from 100 thousand. Km. and more note the slightly increased noise level from the fuel pump. The fuel pump may buzz or whistle louder when the ignition key is turned. In parallel, there are problems with starting the engine, fuel consumption and smooth reactions to the pressure of the accelerator pedal while driving does not occur. The car practically does not lose in dynamics, allowing you to ride with a buzzer petrol pump more than tens of thousands of kilometers.
At such problems of the pump it is desirable to carry out diagnostics, as constant work with the increased loading causes an overheat of the petrol pump and reduces its resource. At the same time it is not necessary to change the pump at once without check. Replacement of the fuel pump grille and fuel filter, as well as cleaning the injectors in many cases to get rid of noise.
The louder or progressive whistling and hum of the fuel pump is a reason for immediate detection and elimination of breakage, which involves checking the performance of individual elements of the engine power supply system. In this case, the increased noise level of the fuel pump usually occurs for the following reasons:
- dirty fuel filter and fuel pump screen;
- clogged fuel line;
- the motor of the petrol pump fails;
- clogged fuel injectors;
- faulty fuel rail pressure regulator;
We also recommend reading the article about it, how to clean the filter-grid of rough cleaning of the petrol pump. In this article you will learn about the available ways to clean the fuel pump screen with your own hands.
These faults are also often accompanied by poor engine start, unstable operation of the internal combustion engine (the motor triples) at idle and under load. There are jerks, failures and delays of the engine's response to accelerator pressure. In such a situation, the car becomes difficult and even dangerous to operate, as it is possible to calm down unexpectedly or to get into an emergency situation at attempt of overtaking.
Make a lot of noise at the fuel pump: troubleshooting
In most cases, the increase in noise is due to the increasing load on the fuel pump, which becomes more difficult to pump the required amount of fuel. Overheating or failure of the pump itself is less common.
At the initial stage it should be understood, what if the fuel pump makes a sound (although different from normal), then power is supplied to the device and the pump itself responds to electricity. Based on this, the problem can be localized faster. It is recommended to replace the fuel filter before diagnosing, to eliminate the possibility of reducing bandwidth in this area.
It is necessary to begin check of the pump for fuel supply from that, that you need to measure the fuel pressure in the fuel rail with a manometer. The average value is the pressure in 3 atmosphere. This method allows you to accurately assess the performance of the fuel pump.
There is also a simple solution, which allows you to quickly check the status of the device. The method is, removable return hose and inserted into a separate container, which is suitable for filling with gasoline. Next you need to detect, how much fuel is drained back into the tank. The norm for many gas pumps is the minimum value on the mark from 1.5 liters per minute or more. The disadvantage of such measurements can be considered quite approximate evidence, which do not allow to obtain accurate data.
If the test showed, that the pump does not deliver the necessary pressure or constantly works for its maintenance, then you need to change or clean the fuel pump screen. To do this, you will need to remove the fuel pump, which is usually located in the back of the car under the seat. pay attention, that on cars, which are in operation for a long time, in parallel with replacement of a grid it is necessary to wash the gas tank. The point is, that dirt and deposits will quickly disable the new filter.
After replacing the pump filter or cleaning it, you should also check the pressure regulator in the fuel rail and clean the injector nozzles.. In most cases, these procedures can reduce noise or almost completely eliminate the whistling and hum of the fuel pump. If the pump continues to make noise, then there is a high probability, that the pump motor needs to be replaced.
Replacement of the motor of the petrol pump
The reason for replacing the motor of the fuel pump module is low gasoline pressure or abrupt pressure changes, fixed by a manometer in the diagnostic process. Also, the rapid failure of the motor indicates that, that the fuel pump is buzzing or whistling.
In this case, you can often not change the pump assembly, which will save money. The device must be removed (similar to the situation with cleaning or replacing the mesh filter), after which it is disassembled. The motor itself is changing, which can be purchased separately. The housing and fuel level sensor can be left from the old fuel pump. In parallel, it is recommended to replace the gasket gasket and other rubber seals, which are not intended for reinstallation after removal, that is, they are disposable.
The fuel pump does not switch off and overheats
One of the most common problems is that, that after turning the ignition key the fuel pump does not switch off, that is, it buzzes constantly. In the list of the main reasons autoelectrics allocate:
- burning (sticking) contacts of the controlled circuit of the fuel pump relay;
- short circuit in the wiring to the pump;
Failure of the ECU or pressure sensor on the pump is less likely to occur (depending on the BN device of a particular car), which also makes the fuel pump run constantly. Nozzles can be another reason, which "pour", which does not allow the naos to create pressure in the ramp and start the engine. You can check the condition of the spark plugs. If the candles are flooded, then check the injector chain for breakage.
The relay of the petrol pump is checked simply enough. A working element in a working system clicks through 3-5 sec. after the inclusion of inflammation, after which the pump is switched off. If the relay does not click or there is a click, but the pump does not switch off, then the relay must be removed. Stopping the pump will indicate the failure of the specified relay. You can also get a relay and tap it lightly, in parallel dropping the terminal from the battery. This method often solves the problem of sticking to the fuel pump relay.
Now a few words about the pump overheating. If the fuel pump on the injector overheats, this is manifested in a decrease in its performance and unstable engine operation. The electric petrol pump itself is submersible, that is, it is in the fuel tank directly in the gasoline. This arrangement allows the device to efficiently cool in the fuel. Low fuel level below 1/4 the tank at active operation of the vehicle in the conditions of high external temperatures can cause such overheating.