The best diesel engine cleaner

Improve power and increase fuel efficiency with a good diesel fuel cleaner.

diesel engine cleaner

by Ryan Gilmore |
Updated on

The unmistakable clatter of a diesel engine is becoming a rarer sound nowadays. Demand for diesel is collapsing as politicians compare diesel pollution levels to that of the Chornobyl disaster. Even the white van man, who for years was fiercely defensive of the increased economy of diesel, is switching to hybrids or even to fully-electric offerings.

Until 2030, there will be a place on our roads for diesel cars. If you're travelling long distances on motorways, the fuel efficiency of a diesel engine is almost unbeatable. Diesel may not be popular, but it is important.

One of the drawbacks of diesel, however, is carbon deposits that naturally build up over time. These hard carbon deposits reduce performance and engine efficiency, so it's a good idea to get them removed. Thankfully there are a number of fuel additives available that'll flush these deposits out as you drive along.

We've already covered diesel injector cleaners, but there are more additives designed for different purposes. Let us guide you through the best diesel engine cleaners on the market.

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The best diesel engine cleaners

Best general diesel engine cleaner

STP 5in1 Diesel Cleaner

Rrp: £18.99

Price: £13.99
Alternative retailers
Halfords£18.99View offer


A diesel engine's equivalent of a juice-cleanse, the STP 5-in-1 cleaner will flush out deposits,


  • Great for removing deposits
  • Improves engine power


  • MPG boost is debatable

Best cleaner for turbo diesels

Wynn's Diesel Turbo Cleaner

Rrp: £11.99

Price: £11.60
Alternative retailers
Halfords£12.99View offer


If your turbocharged diesel engine is missing some boost (sorry), then it may be partially blocked


  • Helps restore performance
  • Helps save turbochargers from expensive replacement costs


  • Only works with turbo diesel engines

Best diesel injector cleaner

Forte Lubricants Car Diesel System Specialist Injector Cleaner

Rrp: £18.99

Price: £17.40


Injectors are one of the first things to clog in diesel engines and will affect performance and


  • Formulated to help with cold conditions


  • Rather an expensive option

Best aid for particulate filter

Wynn's Diesel Particulate Filter Cleaner

Rrp: £12.49

Price: £10.49


A diesel particulate filter (DPF) will reduce soot emissions and make a diesel engine cleaner.


  • Reduces soot emissions
  • Avoid DPF maintenance costs


  • Doesn't target other areas of the engine

Best for high-mileage diesels

STP high mileage injector cleaner

Rrp: £6.49

Price: £5.99


As cars get older, they inevitably start to run less efficiently. This highly concentrated


  • Perfect for cars with over 75,000 miles on the odometer


  • Newer/low-mileage cars will not show any difference

Best EGR cleaner

Wynn's Diesel EGR cleaner
Price: £7.46


The EGR (Exhaust Gas Recirculation) system reduces harmful Nitrogen Oxide emissions (N2O) and is


  • Reduces harmful emissions
  • Helps avoid hefty EGR repair bills


  • Not added to fuel
  • Will not help injectors or performance

Best cleaner for helping reduce emissions

Cataclean diesel DPF and catalytic converter cleaner

Rrp: £17.49

Price: £15.62


Perfect for reducing emissions, Cataclean is designed to clean and protect your car's catalytic


  • Reduce emissions and increase fuel economy


  • Negligible performance improvement

What you need to know about diesel engine cleaners:

The exhaust pipe from a diesel car
©Photo: Getty Images

Why do you need diesel engine cleaner?

Diesel loves to create nasty carbon deposits over time which will make your engine less efficient. The tell-tale signs include black smoke and reluctance during starting. An engine full of deposits will also suffer from less performance and increased fuel usage. That's why these fuel cleaners are so useful, they help dissolve these deposits and restore performance and efficiency.

How to know what engine cleaner to buy

It can be quite hard to diagnose where the deposits are building up in your engine, so for most applications, a generalised cleaner will probably be better.

If, however, you can pinpoint the issue, a specialised engine cleaner will have insanely good results. Here are the common warning signs:

If your running a turbo diesel engine and can feel a noticeable loss of power, there's a good chance the turbo could do with a cleanout**.**

Struggling on start-up and black smoke from the exhaust points to an injector problem. Invest in some injector cleaners to prevent these issues.

MOT coming up? If you're worried about emissions, then a catalytic converter cleaner could make the difference between a pass and a fail.

What's the best diesel car ever?

A question that's not asked as much as it should, some fantastic dino-juice cars are in the back pages of automotive history. To answer this very important question we've

I'm championing the Alpina D3 S (in green, obviously) and the utterly stupid but interesting Audi Q7 V12 TDI.

Chris Williams has chosen the BMW 530d and the Ford Ranger Raptor, an ideal two-car garage for doing nearly anything.

Adam Binnie comes in strong with the VW Amarok V6 and the Audi S6 Avant TDI. The all-German alternative to Chris' choices. It seems a pattern is emerging, one sensible motorway-eating estate and one tackle-anything SUV (although the Q7 would probably break down or run out of fuel long before off-roading).

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