Diesel injectors play a crucial role in the smooth running of your car’s engine. They are responsible for spraying fuel into the combustion chambers with millimetre precision. A clean diesel injector in good condition can significantly improve your vehicle’s performance, increase fuel efficiency, and reduce pollutant emissions. In this article, we’ll explore in detail how to test, clean, and choose the best product for diesel injectors, to optimise your car’s performance.

1. How to test a diesel injector:

Knowing whether your diesel injectors are working efficiently is essential to identifying potential problems affecting your vehicle’s performance. Here’s a simple way to test your injectors:

Listen for unusual noises: Excessive knocking or popping noises can indicate injector problems.

Monitor engine performance: Misfiring, erratic acceleration or a loss of power could be linked to a faulty injector.

Analyse emissions: Excessive black smoke and increased fuel consumption can be signs of dirty or faulty injectors.

For a more accurate diagnosis, we recommend that a compression test is carried out by a professional.

2. What is the best product for cleaning diesel injectors?

Regular cleaning of diesel injectors is essential to maintain their optimum performance. There are various cleaning products on the market, but the best choice depends on your needs and budget. Here are some popular options:

Fuel cleaning additives: These products can be added directly to the fuel tank. They clean the injectors by removing carbon and soot deposits.

Professional cleaning: If your injectors are very dirty, consider having them professionally cleaned by a car care specialist.

3. How to clean diesel injectors:

Here’s a simple way to clean diesel injectors using a fuel-cleaning additive:

Choose the right product: Select a quality cleaning additive suitable for diesel engines. Wynn’s offers the option of Diesel Injector Cleaner: the classic cleaner, tried and tested for years.

– Pour the additive into the tank: Simply pour the whole bottle into your fuel tank. Ideally, at the same time as refuelling, but it’s not compulsory. Fill up the tank to allow the additive to be correctly distributed throughout the fuel system.

Drive your car: Drive far enough to allow the cleaning additive to circulate through the system and clean the injectors. The treatment is considered complete when the vehicle consumes all the fuel.


Well-maintained diesel injectors can significantly improve your car’s performance by ensuring efficient and clean fuel combustion. By regularly testing your injectors, using the right cleaning products, and following the correct procedures, you can keep your injectors in good working order and enjoy a smoother drive, better fuel economy and reduced harmful emissions.

Don’t hesitate to seek professional advice for persistent injector problems.