
Our Mercedes A-Class gets the EDT Treatment
We’ve taken one of our own cars – a 2007 Mercedes A180 with 95,000 miles – for an EDT engine decontamination treatment. Does it deliver on its promises?
2017 UPDATE: It’s two years since we had our own car treated by EDT, so we thought we ought to update this article and make it more current. You can read that update at the end of this review.
Long gone are the days when cars needed a regular de-coke to keep them running, and with modern engines and modern oils we’ve all got used to just having regular servicing, with no special additional work needed to keep our cars running well.
But a new company – EDT Automotive, established in the UK in 2013 – have a machine that will clean the inside of your engine (they liken it to de-scaling a dishwasher) with claims the treatment will reduce emissions, improve performance and give you better mpg. Which all sounds a bit too good to be true.
We’ve been impressed by the claims for the EDT treatment, but all common sense tells us it’s likely to be all about clever marketing, and the positive reviews from customers who’ve had the treatment more about them experiencing what they expected after swallowing the pre-sales banter.
So although we always try to have an open mind when we review anything, we did come at this with a fair degree of scepticism.
To make EDT’s job a bit more difficult, we decided to take along a car we use for lots of little local journeys – a 95,000 mile Mercedes A180 diesel – which is still in decent nick but smokes a bit, is a bit ragged round the edges and doesn’t have the get up and go it once had (which sounds a bit like most of the Cars UK staff).
EDT sent along Shaun, one of their team, to supervise the work – kindly undertaken by the very able Antony Servis at Dukes Park Automotive in Chelmsford – and we turned up with our little A-Class, deep down expecting to be disappointed and to find no real tangible changes in the car after the treatment.
The treatment is very straightforward, with the oil drained as normal before connecting up the EDT machine to the oil filter housing.
The machine then pulse-pumps soya oil (so there’s nothing chemical that could cause damage) through the engine, heated to 42 degrees at 40PSI (pressure and temperatures that are well below those your engine is used to dealing with) in three cycles.

The EDT Filter before and after treatment
The first cycle circulates the soya oil through the engine, the second cycle is a soak and the third a recovery. It all takes less than 15 minutes to complete and it’s astonishing how much additional gunk is cleared out.
Antony let the oil drain from the sump for longer than the EDT treatment took, despite which the EDT filter ended up thick with sludge (as you can see in the picture), sludge recovered from the engine that would never have come out with just an oil change.
It’s all very slick and professional, and there’s no doubt the process does clear debris, varnish and plenty of muck from the engine. But there are millions of cars on the road that survive perfectly well with just an oil change, so what difference can giving the engine’s internals an extra thorough clean really make?
We tried hard to find no difference after the EDT treatment, but we failed. The differences weren’t just slight, they were significant.
The little A-Class appears to have packed up smoking, it’s noticeably quieter and it’s much, much nicer to drive.
Most noticeable is the pick-up at low revs; where the car struggled to pull, especially ‘off turbo’, it now pulls much more strongly from low speeds at low revs, but even at higher speeds in sixth – where we did have to drop a gear when baulked – it now recovers its speed easily.
We were confused (it happens easily) by an apparently improved gear change. How could cleaning the inside of the engine have any impact on that? Were we imagining it?
It appears that an improved gear change is something EDT – and Antony – have experienced before, and they both put it down to an improvement in torque delivery after the clean. It’s a benefit we didn’t expect, but one we’ll take.
The A-Class also seems to be getting about 5mpg more than before. It’s not huge, but added to how much better it is to drive, it’s a great plus. We also have no doubts that the car’s ‘cleaner’ too, with EDT’s figures of a reduction in CO2 of 59 per cent and 81 per cent in hydrocarbons fully believable.
For those of you old enough to remember when a full service on a car made it feel like it had a new lease of life – when plugs, points, tappets, carb tweaks et al were done – the EDT treatment is the closest you get to that feeling with a modern car.
But perhaps a very non-technical response to how the car feels now, compared to before, sums it up.
The A-Class is used every day by our chief organiser, a lady who keeps us all in check and does the boring stuff. She loaded her dogs in to the car for a short trip to the local woods soon after we got back. Her verdict was simple: “The car feels like it’s smiling”, she declared.
Of course, the big question is: “Would we spend our own money to have an EDT treatment done?” Damn right we would. It costs around the same as the oil and filter again, which makes it as cheap as chips for the impact it has.
And, for once, we’re happy to have been proved wrong. The EDT treatment really does deliver.
EDT Engine Clean Video – Produced by ITN
EDT Automotive – 2017 Update
It’s two years since we sent our little A-Class off to get EDT’s engine clean, and so impressed were we with what it delivered that we’ve kept a weather eye on EDT ever since.
Having established, in the space of two years, a convincing business which delivered on its promise, it would have been easy for EDT to take the route of least resistance, let excellent reviews (like ours, still getting thousands of views two years on) convince potential customers, and rake in the profits.
But actually, EDT are doing the right thing by working hard to improve on the already highly effective engine clean system, adding new products and rolling out to even more service garages – independent and main dealer.
New EDT Engine Clean Machine
Since we used EDT’s services, they’ve launched a new machine (pictured right) which manages to improve on the already impressive abilities of their first generation cleaner, and introduced a machine which will do the same for automatic gearboxes as the original EDT machine did for engines.
The new machine cleans even more effectively, filtering to 3 microns instead of 5 (a 40 per cent improvement), with that ability retro-fitted to the existing EDT machines and, although it only really matters to the chaps doing the treatment, it’s quieter, fully electric and better looking.
Automatic Transmission Cleaning
Using the same technology as the engine cleaner, the new automatic transmission cleaner does the job of removing the old oil, cleaning the gearbox and refilling with new oil.
Impressively, the EDT machine removes at least 78 per cent of the old oil (manual fluid changing manages 60 per cent at best), which probably makes it worth the cost for that alone.
Conclusion
It’s good to see that everything we discovered when we did this review two years ago still applies, and to see a business that actually seems to care about its customers and partners.
That’s demonstrated with the diverse awards EDT has won, with The Green Organisation Award for reducing emissions, Top Product Award from Professional Motor Mechanic Magazine, and a 9.8 rating on Trust Pilot. So the green lobby happy, the garages using it happy and customers happy too. Blimey, that doesn’t often happen.
We’ll keep watching EDT, but we’re happy to say they are an even better bet now than they were in 2015.
And they’ve now done over 36,000 engine cleans in the UK, so we reckon they’ve probably got the hang of it.
Garages on Cars UK offering the EDT Treatment
Bedfordshire
Jackson & Phillips
Dorset
Hypermotive – Bournemouth
East Sussex
Morris Road Garage – Lewes
Essex
Mercury Car Centre – Brentwood
Dukes Park Automotive – Chelmsford
Oakdene Autos – Basildon
Glasgow
KP Autos
Greater Manchester
Egerton Garage – Whalley Range
Hampshire
Premier Car Care – Romsey
Hertfordshire
Bushey Hall Garage – Bushey
Kent
Tomsett Kent
Monmouthshire
DMS Auto Services
Northumberland
Cavendish Motor Company Limited
Oxfordshire
Courtneys Garage
Perthshire
Strathearn Engineering
Surrey
Harding Auto Services – Woking
Staffordshire
AWJ Automotive – Stoke-on-Trent
West Midlands
Hollier & Sons
Cardinal Motors
EDT treatments are offered Nationwide. Check out EDT for more information.
Disclaimer: EDT Automotive is a Cars UK advertiser, but this is NOT a paid for article.
charlie apps (taxi driver) says
I would like to have this treatment done on my 4 year old skoda superb (154000+ miles) but find £130:00 on top of the service price a bit much.
malcolm tanner says
Had my car edc cleaned today unbelievable results the engine instantly sounds quarter and runs smoother plus the engine used to smoke on idle seems to have stopped very impressed
Barry Blue says
i think this sounds ok so seriously thinking of having it done. dont like main dealers so wehers the nearest garage to me in weybridge?
Gary says
Hi Barry, Thank you for your enquiry, the nearest sites that has 1 of our machines is either Aldershot Peugeot or Kingston Toyota. If you can give me a call on 01233 712341 we can get the details of your car and make the arrangements for you at either location and 1 of our team would meet you there.
Barry Blue says
thanks for that. maybe by the time the cars ready for a service again you’ll have someone whos not a main dealer.
David Holmes says
13,000 cars treated in the UK and we have never had an complaint yet !! 1000 cars a month we are very confident of our unique product !!
RogerH says
Question: if the treatment takes out stuff left behind in an oil change does it leave behind bits of the soya oil when it’s finished too? What does having traces of the soya oil left do to the new oil?
David holmes says
Hi Roger the machine and pumps are air operated and on its final cycle the engine is purged of all the fluid by vacuum and air so only a film is left but in any event it is only a 2 wieght oil itself and is harmless .Hope that answers your question ?
RogerH says
That makes sense.
chathamjohn says
Are the improvements you found still there orr was it just a first flush feeling (see what i did?!)
Cars UK says
It’s a bit over a week since we had the EDT treatment, and the effects we experienced are still the same.
What has changed is the economy. We reckoned we were getting about 5mpg more than we were, but after more than a week of normal use we’ve averaged 51.3mpg, when we were previously getting 41.9mpg.
‘First Flush’ -.Very good!
Andrew says
I had this done on my diesel Audi A6, and can confirm the improvements were very much in line with the ones you’ve experienced. Agree it’s worth paying for, but not sure I’d have it done every service.
Mercedes62 says
Still struggling to believe, but I’ll get round to looking for someone in my area to do and give it a whirl! Was it really that noticable the difference?
Cars UK says
It was. We really weren’t expecting to find any real improvements, but it has really perked the car up.
David says
The only way you will be convinced is to have it done ! It will be our pleasure to convert you !
Mercedes62 says
Thank you for making the effort to comment. The review has convinced me to have this done when services are due on the cars. They’re not due until later in the year but once they’ve had it done I’ll let you know. Cheers!
David Holmes says
Your welcome we look forward to shocking you ! Call me direct when your ready I am the MD . David on 07772 046576
Mercedes62 says
I’ll bear that in mind when we’re ready to get this done. You must believe in your product if you’re brave enough to publish your mobile!!