How to Buy Injection and Fuel Systems

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How to Buy Injection and Fuel Systems

A fuel injection system eliminates the need for a carburettor by delivering the fuel directly into the engine's combustion chamber. Fuel injection has been around since the 1950s and widely used on European cars dating from around 1980. Fuel injection systems are more fuel efficient and environmentally friendly than a carburettor. The system is made up of a fuel injector, or electronically controlled valve, which is supplied with pressurised fuel and is capable of opening and closing multiple times per second. The pressurised fuel is squirted through a tiny nozzle, which atomises it. The length of time that the fuel injector stays open determines the amount of fuel that is supplied to the engine.

Modern fuel injection systems are specifically designed for the type of fuel being used. Some systems are designed for several grades of fuel, while others require a specific type: they may be geared towards petrol or diesel. When purchasing a fuel injection system at retailers such as eBay, buyers should consider the various types, familiarise themselves with the different sensors, take into account the advantages and disadvantages of using this system, and learn how to clean the fuel injection system for optimal performance.

Types of Electronic Fuel Injection System

There are various types of electronic fuel injection system. Each type varies in the way that fuel is delivered to the combustion chamber. Choosing the best type is often a matter of personal preference, the desired fuel efficiency, and vehicle compatibility.

Throttle-Body Fuel Injection System

Carburettors were first replaced by throttle-body injection systems. A throttle-body injector performs the same function as a computerised carburettor. It has a single fuel injector that delivers fuel to all of the combustion chambers at set intervals of time. The throttle-body injector sits on top of the engine. When this system was created, it limited the number of alterations that car manufacturers had to make to their engine designs.

Multi-Port Fuel Injection System

Multi-port fuel injection systems have a separate fuel injector for each cylinder. Although the cylinders do not all fire simultaneously, all fuel injectors spray fuel at the same time. This type of fuel injection system is more advanced than throttle-body injection.

Sequential Multi-Port Fuel Injection System

Sequential multi-port fuel injection systems are the most advanced type of system. Unlike the multi-port fuel injection system, the injectors in this system spray immediately before a particular cylinder fires. This creates a faster response time when the driver of the car floors the accelerator. It also provides more accurate fuel metering.

Types of Fuel Sensor

Each electronic fuel injection system is operated by a computer that controls the intervals at which the injectors spray and how much fuel is delivered. Sensors then send important information back to the computer for processing. These sensors and their tasks are listed in the table below.

Type of Fuel Sensor


Mass airflow

Tells the Engine Control Unit (ECU) the mass of the air entering the engine


Monitors the amount of oxygen, or unburned fuel, in the exhaust so that the ECU can determine how rich or lean the fuel mixture is and make adjustments as deemed necessary

Throttle position

Monitors the throttle valve position so that the ECU can respond quickly to changes, increasing or decreasing the fuel rate as necessary

The further down the accelerator is pushed, the faster the engine goes, and the more frequently the fuel injectors must spray

Coolant temperature

Allows the ECU to determine when the engine has reached its proper operating temperature


Monitors the system voltage in the car so that the ECU can raise the idle speed if the voltage is dropping

Manifold absolute pressure

Monitors the pressure of the air in the intake manifold

The more air that goes into the engine, the lower the manifold pressure

Gauges how much power is being produced

Engine speed

Monitors engine speed

Helps to calculate the pulse width

Although an electronic fuel injection system is much more complicated and is more computerised than a carburettor, it offers buyers a wide array of benefits. The sensors allow for more precise fuel delivery, which in turn allows drivers to be more environmentally friendly. By preventing superfluous fuel from flowing into the car's engine, drivers are not only protecting the air quality by cutting down emissions, but also conserving fuel. In addition, fuel injectors give cars more power and acceleration.

Advantages of Injection Fuel Systems

Fuel injection systems offer a more dependable engine response during quick throttle transitions as well as easier and more dependable engine starting. Injection fuel systems also operate more efficiently at extremely high or low ambient temperatures.

Disadvantages of Injection Fuel Systems

While injection fuel systems offer many benefits, some people still prefer the carburettor. A carburettor contains jets that push the fuel into the combustion chambers. Carburettors last longer than fuel injection systems and are often preferred for motor sports. This is due to the fact that they are much simpler to install and less expensive to repair. Unlike fuel injection systems, carburettors have no electrical components or return lines to the fuel tank. Overall, the low cost of the carburettor greatly contributes to its continued desirability.

Cleaning a Fuel Injection System

It is important to clean a car's fuel injection system periodically. As the fuel injector acquires dirt and grime, the amount of energy it receives from the fuel is reduced. In addition, the fuel injector may begin to emit more pollution and ultimately affect the performance of the car. Drivers can have their fuel injection system cleaned professionally or can clean it themselves.

When cleaning a fuel injection system, buyers should always take safety precautions because it involves working with acidic cleaning solvents. It is a good idea to invest in a pair of safety goggles and gloves to protect the skin. Cleaning solvents are extremely flammable, so buyers should avoid using them around an open flame or excessive heat.

To begin the cleaning process, first switch off the car engine and lift the bonnet to access the engine. Once the fuel injection system has been found, disconnect the fuel pump to stop the flow of fuel to the engine. Then connect the pressurised solvent to the engine. In order for the solvent to clean the engine thoroughly, start the car. Once the engine has been cleaned, switch the car off and remove the cleaning solution. Finally, reconnect the fuel lines and the fuel pump and run the engine to check the performance level. Once the fuel injection system has been cleaned, there should be a noticeable difference when the car is running.

How to Buy Injection and Fuel Systems on eBay

There are many different injection and fuel systems on eBay. Buyers can search for these car components on the eBay home page. From here, buyers can input search terms such as "fuel injection system" to help them to locate the best system for their requirements. Buyers can then use eBay’s filters to further narrow down results by condition, price, or features of the injection and fuel system. Using these filters saves the buyer from browsing through the large selection of systems that eBay has to offer. As an alternative, buyers who know specifically which item they require can enter more specific search terms.

Buyers should examine the condition of the injection and fuel systems carefully before making a purchase. If any additional questions or clarification is needed, then buyers are free to contact the item’s seller directly by using the "Ask a question" feature. If the system is being sold close to home, then buyers can ask the seller if they can view it to check the type and condition before purchasing. This gives buyers the opportunity to test the fuel injection system to see if it is a good fit for their car.


Buyers hoping to improve the fuel economy of their car should consider replacing their carburettor with a fuel injection system. Most modern cars already operate with a fuel injection system. However, older cars, especially those manufactured before the 1980s, may still have a carburettor. Fuel injection systems are also ideal for environmentally concerned drivers as they decrease pollutants that are emitted into the air. When searching for a fuel injection system, buyers should first consider the various types. Some types, such as the multi-port fuel injection system, are more advanced than others.

Buyers should take into account the type of petrol that the fuel injection system uses and the car's compatibility. In addition, buyers should familiarise themselves with the various sensors that help the system to optimise its fuel efficiency. On balance, the advantages of a fuel injection system far outweigh the disadvantages. In order to keep the car running smoothly, buyers should learn how to clean the injection and fuel systems. With so many systems to choose from, eBay can help every buyer to find the perfect one to maximise their fuel efficiency and increase the power of their car.

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