How to Tell if Your Diesel Fuel Injectors Need Replacing

February 1, 2022

As any diesel owners knows, the integrity of the fuel you use can play a major role in the performance of not only your engine, but also your diesel’s performance overall. Using high-quality diesel will ensure your car runs smoothly, and helps you avoid expensive repair costs down the line.

But what if you only ever use good fuel and still notice a decline in performance? Unfortunately, the next component to check would be your fuel injectors, which can become clogged up over time, interfering with your engine’s fuelling and its performance. If the precision of your fuel injectors has been compromised by electrical issues, restrictions, or fuel problems, you will start to experience drivability problems.

How can you tell if your fuel injectors are clogged and need replacing? Find out below!

How to Tell if Your Diesel Fuel Injectors Need Replacing - mechanic working on engine

What is a Diesel Fuel Injector?

A diesel fuel injector is a precision device that sprays fuel into your engine at just the right rate and time. Injection of fuel into the engine is critical in ensuring optimal performance from your vehicle, as well as reducing emissions output.

Read More: Benefits of Upgrading Your Common Rail Diesel Fuel Injectors

Why are Diesel Fuel Injectors Important?

By injecting a precise amount of diesel at precisely the right time, your injectors help to optimise power and torque along with reducing harmful emissions. Diesel has a high ignition point which means it does not combust easily unless injected under extreme pressure inside the combustion chamber of the engine.

As a result, diesel engines need an electronic control system to monitor many parameters such as throttle position, rail pressure and air intake etc., in order to function properly.

Diesel Fuel Injectors are Vulnerable to Clogging

With time, or due to poor quality fuel being used, your diesel fuel injectors can become clogged. This is because the precision-machined holes of the injector can become partially blocked with diesel soot particles.

Diesel soot is one type of carbon particle that forms as a result of incomplete combustion in the engine. Other types of carbon include brake dust and road film which contaminate your engine oil and accumulate within your injectors overtime.

Read More: Top 5 Must-Do Maintenance Tips for Diesel Engines

How to Tell if Your Diesel Fuel Injectors Need Replacing - oil filtering out of car

How to Tell if Your Fuel Injectors Need Replacing

A faulty common rail pressure sensor can cause problems for your car’s performance, but there are several other telltale signs that you need new fuel injectors.

Read More: 5 Signs Your Diesel Engine Needs a Performance Facelift

You Experience Fluctuations in Power

If you notice a loss of power during your vehicle’s performance, it may be due to dirty diesel fuel injectors. However, faulty sensors and other components can also cause such problems so this is not necessarily the only symptom to look out for.

You Notice an Increase in Exhaust Emissions

Diesel soot particles clogging up your fuel injectors causes exhaust emissions to rise as well as decrease the engine’s combustion efficiency and consequently its horsepower and torque output. Additionally, turning off your car and restarting it will create more unburnt carbon waste that further pollutes the air we breathe.

Your Engine Hesitates When Accelerating

Clogged diesel fuel injectors also cause hesitation when accelerating from stationary, which can be dangerous in certain situations.

Your Car is Noisy When it Runs

A clogged up and faulty diesel fuel injector also affects the smooth running of your engine and in some cases, may cause knocking sounds to emit from the cylinders when accelerating.

Knocking is caused by unburnt carbon releasing into the combustion chamber. Over time, this can damage key components such as piston rings and valves at considerable repair costs.

Read More: What is a Diesel Engine Tune Up?

How to Tell if Your Diesel Fuel Injectors Need Replacing - mechanic in front of car with gloves on

Book Your Diesel in at Our Workshop

Struggling with poor responsiveness from your diesel? Does putting your foot flat no longer make the difference it used to? You may need to have new fuel injectors installed!

Contact the Just Autos team to discuss your power and performance needs. Our experienced team can help assess any existing problems with your vehicle, as well as provide advice on how best to care for it and inform you of upgrade and modifications options available for your particular car.

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