Cranbrook Cars Advice & Guides
By Cranbrook Cars (City & Guilds qualified mechanics, CVTS registered, The Common, Sissinghurst, Cranbrook TN17 2AF) · Last reviewed: November 2026
In EDT engine cleaning vs carbon cleaning, the two treatments clean different parts of your engine: EDT engine cleaning flushes the internal wet oil system in about 15 minutes before an oil change, while carbon cleaning treats the dry air intake and exhaust path and is recommended roughly every 15,000 miles for high-mileage drivers. Book either at Cranbrook Cars, Sissinghurst.
At a Glance: Key Facts
- EDT Engine Cleaning: Cleans the wet oil galleries & sump using a mineral-oil flush (about 15 mins in our workshop, plus new oil & filter)
- EDT Carbon Cleaning: Cleans the dry air intake, valves, combustion chamber & exhaust (about 30–60 mins in our workshop)
- Manufacturer’s Emissions Claim: EDT Automotive states average reductions of 69% in CO & 61% in diesel smoke
- Recommended Carbon Interval: Our workshop recommends roughly every 15,000 miles for high-mileage and business drivers
- Engines Covered: Non-invasive treatments with no engine dismantling; ask us about your petrol, diesel or hybrid engine
Table of Contents
How Do EDT Engine Cleaning vs Carbon Cleaning Compare Side by Side?
Drivers often ask us about the difference between EDT engine cleaning vs carbon cleaning because both improve fuel economy, restore throttle response, and reduce exhaust emissions. Here is how the two treatments compare at our Sissinghurst workshop:
| Comparison Point | EDT Engine Cleaning (Oil System) | EDT Carbon Cleaning (Intake & Exhaust) |
|---|---|---|
| Which part of the engine it cleans | The internal lubrication / oil system (oil galleries, piston rings, hydraulic lifters, and sump). | The air intake, combustion, and exhaust path (intake manifold, valves, pistons, and exhaust). |
| What deposits it removes | Thick black oil sludge, varnish, and microscopic metallic debris left behind by gravity oil drains. | Hard baked-on combustion soot, carbon deposits, tars, and gums. |
| How the process works | Circulates heated mineral oil through the engine’s oil system, followed by a new filter and fresh oil. | Introduces a cleaning liquid into the intake and exhaust system while the engine runs. |
| Typical workshop duration | In our workshop, about 15 minutes (plus fresh oil and filter change). | In our workshop, about 30 to 60 minutes depending on engine size. |
| When to book | Alongside your annual car service or when buying a used/older vehicle with unknown oil history. | Our workshop recommends roughly every 15,000 miles for high-mileage and business drivers, before an MOT emissions test, or after lots of short stop-start journeys. |
How Does the 15-Minute EDT Engine Decontamination Machine Work?
During a standard oil change, draining the sump removes most of the old liquid oil, but sticky sludge and varnish remain clinging to internal engine surfaces. As soon as fresh oil is poured in, it mixes with that leftover residue and turns dark almost immediately. Developed by EDT Automotive, our Engine Decontamination Machine connects to your engine after the old oil is drained and circulates heated mineral oil through the engine’s oil ways, which in our workshop takes about 15 minutes. EDT describes the oil as non-toxic and biodegradable. We then fit a brand-new oil filter and fresh oil. EDT Automotive states average reductions of 69% in CO emissions and 61% in diesel smoke; these are the manufacturer’s figures, not our own measurements.
How Does Intake and Exhaust Carbon Cleaning Work?
Every time petrol or diesel burns in your cylinders, it creates microscopic soot, tars, and gums. On cars that do short hops — such as the daily run to Staplehurst, Marden, or Headcorn station, or school runs around Cranbrook — the engine rarely gets hot enough for long enough to burn those deposits off cleanly. Over many thousands of miles, carbon builds up on valves, piston crowns, and exhaust components, choking airflow and hurting MPG. Our EDT carbon cleaning in Cranbrook safely breaks down and clears those deposits without dismantling the cylinder head.
Which Treatment Should You Book Before an MOT or Service?
When weighing up EDT engine cleaning vs carbon cleaning, the right choice depends on how you use your vehicle:
- Book EDT Engine Cleaning when your car or van is due its oil service, if the oil has gone dark and sludgy, or if you want to protect timing chains, turbochargers, and piston rings with clean lubrication.
- Book EDT Carbon Cleaning (our workshop recommends roughly every 15,000 miles) if you drive a high-mileage business van or taxi, if your diesel or petrol car does mostly short local journeys, or before your MOT test to lower exhaust emissions.
- Combine Both Treatments: Because one cleans the wet oil side and the other cleans the dry combustion side, booking both together gives an older or high-mileage engine a complete internal overhaul.
Where Can You Check These Facts?
- EDT Automotive — Official Engine Decontamination Technology
- GOV.UK MOT Inspection Manual: Section 8 Nuisance (including 8.2 Exhaust emissions)
Related Guides and Workshop Services
- Related Guide: What Happens If Your Car Fails Its MOT? Rules & Free Retests
- Related Guide: Commercial Van & Vintage Car Servicing in Cranbrook, Kent
- Pre-MOT Checklist: Checks to Help Pass Your Car MOT Test
- Matching Workshop Service: EDT Engine Cleaning in Cranbrook
- All Guides: Browse All Car Maintenance, MOT & Repair Guides
Need advice or want to book your car or van into our Sissinghurst workshop? Call Cranbrook Cars on 01580 715007 or send us a message online.
Common Questions
Frequently Asked Questions
What is the main difference between EDT engine cleaning and carbon cleaning?
EDT engine cleaning flushes the wet oil lubrication channels inside your engine with heated mineral oil before an oil and filter change, whereas carbon cleaning clears soot, tars, and gums from the dry air intake, combustion chambers, and exhaust system.
How long do EDT engine cleaning and carbon cleaning take?
In our workshop the EDT engine decontamination takes about 15 minutes (followed by a new oil filter and fresh oil), while intake and exhaust carbon cleaning typically takes between 30 and 60 minutes.
Can these treatments help my car pass its MOT emissions test?
They may help, but we cannot guarantee a pass. EDT Automotive states its Engine Decontamination Machine gives average reductions of 69% in CO and 61% in diesel smoke, and carbon cleaning aims to restore cleaner combustion before an MOT.
Are EDT engine cleaning and carbon cleaning safe for my engine?
Both treatments are non-invasive and need no engine disassembly. EDT describes its mineral oil as non-toxic and biodegradable. Call us on 01580 715007 and we will confirm the right treatment for your petrol, diesel or hybrid engine.
How often should I book carbon cleaning or engine decontamination?
Our workshop recommends carbon cleaning roughly every 15,000 miles for high-mileage and business drivers, and EDT engine cleaning alongside your annual oil service. Call 01580 715007 to book.
Last reviewed: November 2026 by Cranbrook Cars
Would you like to know more?