• Incomplete combustion leaves behind unburnt fuel and oil residues.

• This accumulates as stubborn carbon “gunk” on vital engine components, especially prominent in direct-injection petrol and diesel engines

• Hydrogen (HHO) carbon cleaning

  • Produces hydrogen–oxygen gas via electrolysis, injected into the intake

  • Burns off carbon into harmless water and CO₂ emissions

• Chemical flushing/additives

  • Solvents are added to fuel or intake, dissolving deposits

  • Quick, but risks harming engine coatings or sending debris downstream

• Walnut-blast (mechanical)

  • Crushed walnut shells are blasted onto intake valves (inc. DI engines)

  • Very effective but labour-intensive; may take many hours or cost £1,000+

Manual cleaning

• Disassembling components and physically scraping/soaking them

• Highly effective but costly and time-consuming

• More power & smoother running: Clears airflow and fuel flow restrictions

• Improved fuel economy & lower emissions: Burning fuel more efficiently; easier MOT compliance

• Protection for expensive parts: Prevents premature wear on EGRs, DPFs, turbos, injectors

• Extended engine life: Cleaner internals reduce component strain over time

• Mixed opinions: Auto Express notes results vary—some find it effective; others see little difference

• Petrol vs Diesel: Direct-injection petrol and diesels typically benefit most. Conventional petrol engines less so

• DIY care vs pro service:

• Risks in poor execution: Walnut-blast jobs performed incorrectly can leave debris inside or damage components

• Recommended about every 15,000–30,000 miles or if performance/emissions begin to slip

• Look out for symptoms: rough idle, loss of power, poor fuel economy, black smoke, failing emissions, DTCs

• Regular maintenance + occasional “Italian tune-up” motorway run can delay buildup

• Good for: High-mileage turbo, DI engines with performance/emissions issues

• Less priority: Low-mileage, conventional petrol engines in good condition

• Choose method wisely: Hydrogen or mechanical cleaning are most effective; detergents less reliable

• Get a trusted provider, check reviews, ask for dyno/live data evidence

Carbon cleaning tackles internal engine deposits to restore performance, economy, and reliability. Diesel and direct-injection petrol engines often see the biggest benefits. Methods range from simple chemical flushes to full mechanical walnut-blasting. It’s not a cure-all, but when done correctly – and at the right time – it can serve as a valuable preventive measure and rejuvenation for your engine.

Let us know if you'd like help finding reputable carbon-cleaning services near Cannock or comparing treatment types!