10 Best Fuel Injector Cleaners 2025 in the UK

Wynn's Extreme Diesel System Cleaner is designed to clean the entire diesel fuel system, which includes removing dirt and carbon deposits from key components like fuel injectors and pumps. This deep cleaning helps improve the efficiency of combustion, leading to better fuel economy and reduced emissions. For diesel vehicle owners experiencing reduced fuel efficiency or performance issues due to carbon build-up, this product could be a beneficial choice. It offers an easy 'one tank' treatment, meaning you can simply add it to your fuel without needing frequent application. This makes it a convenient option for those looking to maintain their engine's performance without regular maintenance hassle.

The cleaner is formulated to prevent issues with important engine components such as the turbocharger, EGR valve, and DPF. By keeping these parts clean, it supports better engine efficiency and can help avoid expensive repairs. Additionally, it addresses starting problems by ensuring a smoother ignition process, helping to eliminate rough idling and misfires often caused by a dirty fuel system.

While the product promises a lot, it’s important to acknowledge that effectiveness can vary based on the vehicle's condition and usage pattern. Moreover, some users might find the requirement for consistent usage to prevent future starting problems as a slight downside. With its ability to enhance engine performance, this cleaner stands as a strong option for maintaining diesel engines, particularly if you're facing issues linked to fuel system cleanliness.

The Redex Petrol System Cleaner is a liquid fuel additive designed to clean petrol injectors and fuel systems, making it suitable for petrol and hybrid engines, including those that use E10 fuel. Its primary benefit is its ability to remove harmful deposits that build up inside the fuel system, which can help improve engine performance, increase fuel efficiency, and reduce emissions. This helps extend an engine’s life by keeping it cleaner and running more smoothly.

The product is easy to use—simply pour one 500ml dose directly into your fuel tank, ideally with each fill-up, allowing for regular and hassle-free maintenance. Redex benefits from a long history of over 100 years in automotive care, establishing a trusted reputation supported by strong customer ratings of 4.6 out of 5 from over 6,000 reviews.

This cleaner is most effective for everyday drivers looking to maintain optimal engine health and fuel economy without complicated procedures or additives intended for specialized or high-performance engines.

The STP Ultra 5 in 1 Diesel Fuel System Cleaner is a concentrated liquid formula designed for diesel engines, aiming to improve fuel system performance and engine health. With its concentrated cleaning power, it effectively targets the entire fuel delivery system, restoring engine power and performance by removing harmful deposits. This can be especially beneficial for diesel engines that may suffer from build-up over time, potentially enhancing fuel economy and reducing diesel consumption and exhaust emissions as claimed.

The cleaner also provides protection by reducing friction and safeguarding key engine parts from wear and corrosion, which can result in longer engine life. The product is compatible with diesel engines. A single 400 ml bottle is intended for use with one tank, making it straightforward to use, though users will need to consider how often they should use it based on their driving habits and vehicle's condition.

One notable drawback is the delivery restriction to mainland UK, which could be inconvenient for potential buyers outside this area. The STP Ultra 5 in 1 Diesel Fuel System Cleaner is well-suited for diesel engine users seeking to enhance performance and fuel efficiency as part of regular vehicle maintenance.