Guide to Injectors: what they are, cleaning and replacement for a top-performing engine

The injectors are essential components inside the engine of a vehicle. They are responsible for transferring fuel from the fuel tank to the engine, a process that is crucial to the functioning of the engine.

These small mechanical bodies play a significant role in the fuel system of an internal combustion engine. The efficiency of injectors has a direct impact on vehicle performance, fuel consumption and pollutant emissions. Therefore, understanding how injectors work and how to keep them healthy is of paramount importance to every vehicle owner.

Types of Injectors

There are different types of injectors, each with a specific method of operation. These variations are often related to the type of engine and the fuel used. Here is an overview of the most common types of injectors:

1. Mechanical Injectors

Mechanical injectors consist of a cylindrical body. Inside, a component known as a 'pin' or 'needle' (with a conical tip) is mounted at the end of another element. This needle is actuated by the pressure of a calibrated spring. The fuel arrives at the device from the tank through a connecting body, pushed by the extension moved by the spring. The flow stops when the fuel reaches a ring choke located in the atomisers. The fuel exits the injector as a high-speed, low-pressure jet.

2. Electronic Injectors

Electronic injectors are commonly used in petrol engines and diesel engines with a common rail system. These injectors are electronically controlled and are more precise in their management of fuel flow. Usually, they also have a conical needle, but this needle is actuated by a solenoid controlled by an electronic control unit. The opening and closing of the fuel flow is managed by the ECU, depending on the needs of the engine.

3. Pump Injectors

Pump injectors are used in diesel engines. This technology uses a mixed injection system, combining mechanical and electronic elements. Each cylinder has a dedicated pump, and fuel is injected at high pressure (over 2,000 bar). This system provides an excellent air-fuel mixture, ensuring optimum performance.

Cleaning Injectors

Injectors are prone to the accumulation of impurities in fuels. Therefore, it is important to keep them clean to ensure the proper functioning of the engine. Generally, it is advisable to check the injectors every 20,000 to 25,000 kilometres, which is approximately the same interval between servicing. Cleaning the injectors is part of the routine operations that are carried out during vehicle maintenance.

The accumulation of dirt and impurities can cause problems such as increased fuel consumption, difficulty starting the engine, black exhaust fumes and lower engine performance. If you notice any of these symptoms, it may be time to clean the injectors.

Cleaning Injectors: How It Works

There are two main ways to clean injectors:

1. Use of Additives: Specific additives designed for cleaning injectors can be used. These additives can be mixed directly with the fuel and help to gradually remove impurities. Some products are already available at filling stations and keep the injectors clean for about 5,000 to 10,000 kilometres.

2. Professional Cleaning: If the use of additives does not produce the desired results and the symptoms persist, it is advisable to contact a professional mechanic's workshop. Here, an experienced mechanic will use specialised tools to thoroughly clean the injectors. The cost of this operation may vary depending on the condition of the injectors and the complexity of the disassembly process.

Replacing Injectors

Despite regular cleaning, injectors have a service life and usually need to be replaced before they reach 150,000 kilometres. Replacing injectors is a complex operation that requires the expertise of a workshop technician. On the market, there are specific injectors for different types of fuel (petrol, diesel or LPG), with costs ranging from 150 to 500 euros per new injector.

Conclusion

Injectors play a key role in engine operation. Keeping them in good health is essential to ensure optimal performance, low fuel consumption and reduced pollutant emissions. Regular cleaning and timely replacement, when necessary, are key steps in keeping your vehicle in excellent condition.