Comprehensive Guide: How to Test Fuel Pump​

Fuel pump plays a vital role in fuel power equipment such as automobiles. It is responsible for transporting fuel from the tank to the engine, ensuring that the engine can run properly. Just like the heart of the human body, sending blood to the various organs, the fuel pump provides a continuous flow of "blood" - fuel for the operation of the engine. If the fuel pump fails, the engine may have difficulty starting, lack of power or even be unable to start. Therefore, understanding how to check the fuel pump is very necessary. Thus, we then firstly will find where actually the fuel pump is located.

Where is the fuel pump located​

(1) The location of the fuel pump in the car

In most modern cars, the fuel pump has two main installation positions. One is installed inside the fuel tank, which is more common recently. It is usually integrated with components such as fuel level sensors. The advantage of installing this type of fuel pump inside the tank is that the fuel can be used to cool the pump while reducing the noise of the fuel system. When you need to find this type of fuel pump, you generally need to open the trunk of the car (for some cars), find the access port cover of the tank, and find the fuel pump inside the tank. On the other hand, in some older cars or special models, the fuel pump may be installed outside the tank, near the engine. The fuel pump is usually connected to the inlet and outlet oil pipes, and there will be corresponding electrical connections. If you want to determine the location of this fuel pump, you need to look in the engine compartment of the car and look along the fuel line.

(2) The location of the fuel pump in other equipment

For some fuel-powered small equipment, such as fuel generators, the location of the fuel pump is different. Usually located near the fuel tank of the device, there may be a separate small box or cabin to house the fuel pump. This is in order to facilitate the supply of fuel and the overall structure of the equipment compact.

How much is a fuel pump​

The price of fuel pumps varies depending on a number of factors, including model, brand, size and whether they are original parts. The following are the price ranges for different types of fuel pumps.

As for other equipment (such as generators), the specific price of a fuel pump is different.

H2: How to check fuel pump​

In this section, we will explore in detail how to check fuel pump. The following six steps are common inspection methods for your reference.

Step 1: Check fuel pump location

The fuel pump is usually installed inside the tank of the car, and the exact location varies from model to model. Some models may have the fuel pump integrated on the bottom of the tank, while others may have it mounted on the side or top of the tank.

Step 2: Prepare inspection tools

Before checking the fuel pump, you need to prepare the following tools.

Step 3: Check fuel pressure

Fuel pressure is an important index to judge the working state of a fuel pump. The fuel pressure gauge can be used to measure the pressure of the fuel system, so as to determine whether the fuel pump is working normally.

First, you have to find the fuel pressure test port. Most models have a fuel pressure test port near the fuel rail or fuel filter.

Second, connect the fuel pressure gauge through the adapter and ensure that the connection is tight. Then start the engine. With the engine running, observe the reading of the fuel pressure gauge. Under normal circumstances, the fuel pressure should be within a certain range (specific values can be referred to the vehicle maintenance manual).

Step 4: Check fuel pump relays and fuses

Fuel pump relay and fuse are the key components to control the operation of fuel pump. If the relay or fuse is damaged, the fuel pump will not work properly.

To begin with, you have to locate relays and fuses. Refer to the vehicle service manual to find where the fuel pump relays and fuses are located.

After careful orientation, check the fuse. Pull out the fuse and check whether it is blown. If blown, replace the fuse with a new one. At the same time check the relay by using a multimeter to check the on-off status of the relay. If the relay is damaged, replace it with a new one.

Step 5: Check with a diagnostic device

Modern cars are often equipped with an OBD-II diagnostic interface, which allows the diagnostics to read fault codes and data streams. Through the diagnostic instrument, the working state of the fuel pump can be judged more accurately.

Step 6: Check the fuel pump power supply line

The normal operation of the fuel pump requires a stable power supply. Therefore, checking the fuel pump power supply line is also an important method to judge the working state of the fuel pump.

Locate the fuel pump power supply line: Refer to the vehicle service manual to locate the fuel pump power supply line.

Check the line connection: check whether the line connection is firm, whether there is loosening or corrosion.

Use a multimeter to measure voltage: In the case of starting the vehicle, use a multimeter to measure the voltage of the fuel pump supply line. Under normal circumstances, the voltage should be about 12V.

FAQs

(1) Does fuel pump failure cause engine jitter?

It will be. When the fuel pump fails, it may not be able to provide a stable fuel supply, causing the engine's cylinders to work unevenly, which causes engine jitters. This jitter may be noticeable at idle, or it may occur during acceleration.

(2) Does the fuel pump need to be replaced regularly?

In general, the fuel pump does not need to be replaced as regularly as the oil or air filter. However, if the vehicle is often driven under harsh working conditions, such as long-term driving in a high dust environment or poor fuel quality, the life of the fuel pump may be shortened. In addition, if the fuel pump has fault symptoms, such as starting difficulties, abnormal noise, etc., mentioned earlier, it needs to be checked and replaced in time.

(3) Can I replace the fuel pump by myself?

For those who have a certain amount of experience and skills in automobile maintenance, the fuel pump can be replaced by themselves under the condition of ensuring safety. However, it should be noted that replacing the fuel pump needs to involve the operation of the fuel system, and there are certain safety risks, such as fuel leakage and fire. And, if not done properly during the replacement process, it may lead to new failures in the fuel system. Therefore, if you do not have enough confidence in your ability, it is recommended to go to a professional auto repair shop for replacement.

(4) What are the manifestations of fuel pump failure?

When the fuel pump fails, the vehicle may exhibit the following behaviors.

(5) What do I need to pay attention to when replacing the fuel pump?

When replacing the fuel pump, the owner needs to pay attention to the following points.

Firstly, choose the original factory or reliable quality of the auxiliary parts to ensure the quality of the new fuel pump is reliable, avoiding the use of inferior parts.

Secondly, correct installation is necessary. When installing a new fuel pump, ensure that it is properly installed according to the instructions in the service manual to avoid failure due to improper installation.

Thirdly, check the tightness. After installation, check the tightness of the fuel pump to ensure that there is no leakage.

Last but not least, do not forget to remove the fault code. After replacing the fuel pump, use the diagnostic instrument to remove the fault code to ensure the normal operation of the vehicle system.

(6) How to prevent fuel pump failure?

In order to prevent fuel pump failure, you can take the following measures.

The end

Fuel pump is very important for the normal operation of fuel power equipment. Understanding the location and price of the fuel pump and mastering how to test fuel pump can help us find the possible problems of the fuel pump in time and avoid the abnormal operation of the equipment due to the failure of the fuel pump.