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• Suitable for all diesel engines, AR6400-D MAX contains a proprietary blend of carefully selected detergents that effectively and safely remove deposits from the entire fuel system (fuel injectors, fuel filter, fuel pump, fuel lines), engine, combustion area, glow plugs, turbo, DPF and catalytic converter.
• The above active functions will also help free a problematic EGR and rapidly reduce harmful emissions and unwanted smoke from the exhaust. Resolve engine running issues and restore lost engine performance and fuel economy. Enjoy a smoother and more responsive engine.
• A proprietary blend of multiple MAX-strength detergent functions and post-combustion fuel-borne catalysts ensure a thorough, Professional Grade Clean.
• Additional functions include a proven Cetane Improver using the highest purity UK-manufactured 2-EHN, proprietary ester lubricant, water remover and much more.
• All Archoil fuel cleaners include professional support with a Performance and Emissions Pass Guarantee. Over a decade of success and trusted by professionals.
• Innovation never rests. Archoil formulations are reviewed and updated each year ensuring you always receive the latest advancement in cleaning technology.
A rapid improvement in engine technology has resulted in an imbalance between engine design and fuel quality. This combined with non-optimum driving conditions can result in an accumulation of deposits in the fuel system, combustion area, turbo, diesel particulate filter (DPF) and catalytic converter (CAT). These deposits effect performance, fuel economy, exhaust emissions and engine refinement.
They can also cause engine warning lights or restrictive “limp home” conditions. To address these issues Archoil has released its latest high-strength diesel cleaner, AR6400-D MAX. AR6400-D MAX is a powerful next-generation all-in-one fuel system, engine, turbo, DPF and CAT cleaner. It is the culmination of years of research and the decision to combine the original AR6400-D Engine Cleaner, AR6500 DPF Cleaner and AR6600 Turbo Cleaner technologies providing the greatest value and product performance into a single treatment.
FUEL SYSTEM CLEANER
AR6400-D MAX quickly restores engine performance and fuel economy lost through deposit build-up in key parts of the fuel system, engine and emission control systems. Molecule by molecule deposits are safely removed. AR6400-D Max helps restore variable geometry turbo operation and diesel particulate filter regeneration.
AR6900-D MAX will remove all forms of deposits from fuel injectors including carbons, varnish and stubborn lacquers. AR6400-D MAX will effectively clean older as well as modern Euro 5/6 specification fuel systems. It is suitable for all diesel engines running on pump, bunkered or bio-diesel blended fuel.
LUBRICANT
AR6400-D MAX delivers a modern lubricant helping to protect high pressure injection systems and fuel pumps during the cleaning process.
CETANE BOOSTER & COMBUSTION CATALYST
AR6400-D MAX contains a proven cetane booster to improve combustion efficiency and engine performance, whilst reducing engine noise.
A combustion catalyst technology then facilitates a cleaner burn, improving combustion quality further. These additional functions not only provide an instant improvement in performance but facilitate the cleaning function by keeping recirculating hydrocarbons as low as possible.
FEATURES/BENEFITS:
- Rapidly Cleans Fuel System & Combustion Area
- Removes Deposits from Turbo, DPF & CAT
- Raises Cetane Index Number
- Smooths Rough Idling
- Lowers Harmful Exhaust Emissions
- Lubricates & Protects the Fuel System
- Restores Lost Performance & Economy
USAGE INSTRUCTIONS
- Add the correct amount of AR6400-D Max to the fuel tank first and then fill up with fuel immediately afterwards.
- Treatment ratio is 1:100 > 1:200. A single 400ml bottle will treat between 40 and 80 litres of fuel.
- A 5 litre container will treat up to 1000 litres of fuel.
CAUTION: Do not overdose.
- Use every 5000 miles or use once and follow up regularly with Archoil AR6900-D Max
To browse all Archoil products, follow this link: Archoil – Power Enhancer
Learn more about Archoil here: Archoil
Automotive DPF Cleaner Products
Diesel Particulate Filter (DPF) cleaners are specialized additives and
treatment products designed to help remove soot and particulate buildup
in diesel exhaust systems. These products vary in formulation, dosage,
and compatibility with different engine types. Automotive DPF cleaners
ease regeneration cycles and can improve filter efficiency when used as
directed by the manufacturer.
Top DPF Cleaner Additives with Best Reviews
Across independent test reports and user feedback, certain DPF cleaner
additives consistently receive strong evaluations for effectiveness,
ease of use, and compatibility with modern diesel engines. Reviews often
focus on how well a product supports filter regeneration, reduces
backpressure, and integrates with routine maintenance schedules. Below
we summarize key criteria from professional and community reviews to
help guide informed decisions.
– Michael Blackmore (verified owner)
Very good product, I normally treat products like these with some trepidation, but it works.
Last year my car just about passed the smoke test, this year, passed with no problems.
Car feels better to drive as well.
Thank you.
– Matt (verified owner)
I’ve owned a 2011 plate VW Scirocco 2.0 Tdi Bluemotion with 160k on the clock for just over 12 months & the DPF light was on every other week. I’ve run a bottle of AR6400-D through a full tank of fuel & done a further 1000 miles since and the DPF light hasn’t come back on again. The car does go into regen mode as the revs increase slightly at idle but no DPF light. Also not kicking soot out of the exhaust & can without any hesitation confirm this does work.
– Matt
Having previously used Redex, Wynns, Slick50 and other additives, all with little or no effect, AR6400-D Max was recommended to me on a social media group. My 2017 Audi A5 2.0TDi had poor mpg (low to mid 40s on a mainly fast road commute) and an eco remap had some effect but it still wasn’t where I wanted it to be. This was probably due to build up of deposits during its previous ownership (it had done less than 6k a year over 4.5 years). After one can of AR6400-D Max there was a noticeable improvement in mpg and performance. Combined with regular use of AR6900-D Max (1ml per litre of fuel on every fill up) I’m now seeing low to mid 50 mpg! Can’t recommend it highly enough.
– James
Both the Jaguars I have bought second hand benefited hugely by using Archoil AR6400-D Max intense cleaner diesel additive which was recommended by a friend (I now use it every 3-5,000 miles). Amazing stuff. It transformed the performance of my previous second hand XF 2.2D after 1 tankful. Then I got a 3.0D S and it suddenly started going so much better after 1.5 tankfuls, so i used 3 tankfuls to make sure it had cleaned it well.
They both had a sudden improvement after an amount of the AR6400-D had done it’s cleaning, my theory is that the variable vanes on the turbo were seizing up and suddenly started working properly again, it is the only explanation I can think of for the huge performance improvement!
I now use AR6900-D at every fillup when not using the AR6400-D.
Definitely products to be recommended!
– masif1
Ive been using Archoil for a number of years now, but for the past 1.5/2 years I haven’t used it. When I started using Archoil about 5-6 years ago, it had a different name.
I have a 2006 Ford S-Max TDCi , it has around 130,000 on the clock now and it started suffering limp mode about 5-6 years ago. I came across this website and Archoil after doing a lot of research. I took the car to a number of garages and they all said I need to replace my turbo. I was looking at a cost around £2k. My turbo was suffering from “sticky vanes”.
My car would go into limp mode when travelling mostly on the motorway or dual carriageway where I’d be driving at a constant speed over a long period.
I used Archoil continuously for around 3 months (I don’t do much mileage on my car) I use up on average a full tank of fuel every month.
After using Archoil continuously the limp mode stopped, but I continued using Archoil every 3 to 6 months. I stopped using Archoil abut 1.5 to 2 years ago and the limp mode is back and it’s worse than before. Now the car goes into limp mode even with local driving. And will continuously go into limp mode one after another, very annoying and dangerous. (So dangerous that my wife has stopped using the car).
I’m waiting for the Black Friday deal tomorrow and will be investing good 3 or 6 month supply. I hoping continuous use over 2-3 months will eradicate my limp mode. Otherwise, it’s the scrap yard for the car 🙁
I’ll keep you updated.
– Natty
My 2010 LR4 came up with restricted performance, P0235 and P00BD I think it was. Thought the worst…body off to replace the turbo!
Read alot of reviews on the AR6400-D and as with most things I had a niggling doubt but bought a couple bottle anyway.
Put in 400ml in my tank (fuel warning on so there wasn’t much in it) then filled with 43L of diesel.
Restricted performance stayed on after a few runs, so I stopped, engine off then on again…light still on!
I was thinking by this point I wasn’t that lucky to find a product to work.
So plugged in my diagnostic tool, cleared the fault, tried revving…well, the car shuddered and revs went into the red line!!
NO FAULT LIGHT AND NO RESTRICTED PERFORMANCE!!
WOW, just saved me alot of work!!
Thank you so much!
– Brian
Panicked the DPF light came on ,the car went into limp mode and at 69000miles Skoda Octavia 2012 ,so I spoke a very helpful member of staff at P Enhancer, advised to purchase Archoil AR6400Max, fantastic outcome, the light only came on once again, the RAC technician drove for a 25mile trip keeping the revs up, I needed to cover longer journeys, Covid-19 causes a bit of a problem, but mpg increased 2/3 miles, keep to 70/75mpg what a different car. I now use BP Ultimate diesel. Will be ordering of this company again.
– Peter
Used this in my jaguar s type diesel which was actually running ok but this improved fuel consumption by about 3 mpg so well worth the price I am now using standard diesel instead of premium with archoil ar6900d in every tank saving me about 17 pence per litre and performance improved so great value for money I now average 38mpg compared to 34 mpg before using the additives
– Bob E
I have a 10 Yr old diesel Skoda which for the last 3 years has struggled to get through its MOT because of the stricter exhaust emissions here in the UK.
The government has tightened up the levels required and I’ve used all the usual tricks to lower the emissions by working the engine really hard for a week or so before the MOT to burn off the soot, having an oil and filter change just beforehand and having a propriety fuel cleaner added a few days before the MOT. Despite all this, last year my Skoda just got through the emissions (smoke reading) test by the tiniest of margins. After 4 readings the average was 0.99 where the max allowed is 1.0.
This year I thought I’d try your AR6400 D-MAX. I did the oil and filter change as normal and added your AR6400 D-MAX to a full tank of fuel 3 days before the MOT. I drove approx 170 miles with the additive in and worked the engine hard for those miles during those 3 days.
The emissions test at the MOT this year was brilliant. Less than half of what it was last year (0.41 where the max allowed is 1.0).
So last year the car barely past the test, this year it sailed through easily on the first “fast pass”.
I’ll be buying AR6400 D-MAX again.
– Craig
Now nearly 3 weeks since I added to AR6400 D-MAX to my car and I am pleased to say I haven’t had any limp mode issues since. I give the car a good blast on any stretch of road I can to try and get it to go into limp mode but it doesn’t, so I can honestly say the magic potion appears to have worked. I have some AR6900D-MAX to put into the fuel this weekend. I will review this in a week or so, however I can imagine I will see any immediate benefits as I did with the AR6400, purely using to keep engine/egr and turbo clean
– Craig
Hi, I have been having limp mode issues on my 2002 Golf GTI TDI 150 Anniversary for a month or so now, under load up hill it would lose power, and once you dipped clutch turned off and restarted it was off again with full power until the next time. It was also sluggish on start up in a morning and after work for about a mile or so. Put on vagcom, boost pressure issue. Tested rod to operate vanes in turbo, movement but not as much as you would expect. Tested N75 valve, seemed ok. Must be sticky vanes in turbo.
I put this in on Friday night for my trip from Leeds to Manchester to take son to watch City, I had 1/4 of a tank left and added the 6400 and then filled with 40 litre of fuel. Set off to Manchester about 10.30 had limp mode several times, a bit scary recycling ignition at 70mph. Parked up at about 12. Set back off at 5pm slow traffic for start of journey, only got limp mode once on way back. Sunday had to take partners parents to Manchester airport, we did pick them up last week in her car, however I persuaded her to go in mine. There and back with a 5 min engine stop to unload cases and car never missed a beat. This morning, no plume of smoke from the back on start up, power available from the off. Really impressed. I cant believe I have noticed a difference in 3 days! Need to know what to use going forward to prevent the sticking turbo vanes as only been doing short journeys. The turbo was new 37000 miles ago, so glad this seems to have done the trick. Will up date this review in a few weeks.
Thanks
– Craig
My Discovery 4 was going into limp mode with the variable turbo vanes being diagnosed as the problem. Accessing the turbos on this car means a body off repair which is massively expensive.
Tried carbon cleaning without much luck then tried this product as a last resort. 1 bottle and 40 litres of diesel added to the tank and within 10 minutes of a motorway run the warning light flashed on and off briefly and has never returned. Car is running perfectly again and has genuinely saved me £000’s in repairs. Very impressed.
– Mark
I used AR6400-D followed by AR6900-D Max advanced diesel fuel synthesis in my Mercedes C250 Diesel . The car felt much more responsive after the initial AR6400-D treatment, and then with the AR6900-D really smoothed out the general running with more power ! Very happy man 🙂
– james
I originally purchased a bottle of this to see if it would sort out my troublesome VW Transporter 2.0. DPF light hasn’t been on since so here’s hoping it has done the trick! I have just bought a used XC70 D5 with 140k, though it has a full and extensive service history it chugged on cold idle and sounded like would stall, I put this in the nearly empty tank along with 35litres of diesel and next day it started first turn and idled properly. I’m starting to use archoil 6400d with every fill and I’ll use 6900d every 5000miles to keep a clean engine and hopefully avoid egr/dpf/turbo bills. I was skeptical of this at first but I think age has turned me into a cynic! As long as I have diesel I will use this additive, it also works out cheaper than Shell/Esso/BP premium fuels.
– Philip
Received this product one day after ordering poured it into the tank fingers crossed the miracle liquid would work and make my 2011 ford focus 1.6 tdci sound and run better……TADA it is bloody magic!! Noticed a difference straight away runs sweet and is a lot quieter even the Mrs noticed!! Will be ordering some more never going back to using anything else!!!!
– John
I have used several Arcboil products and my Volvo XC70 D5 Cross Country loves it and mpg is up permanently from 28mpg to 35mpg. I will continue using Archoil treatments.
– Kevin
Never owned a diesel, then after 6 months the fuel filter blocked. Limp mode to the main dealer and it was changed. Looking around I can across this site (and other’s), looked at different cleaners and decided to go with this one and am I glad I did. Full bottle in the tank then filled up. A mixture of long (dual carriage way & motorway) drives with short journeys. It say’s to use every 5000 miles but my next fill up I decided to use my 2nd bottle I purchased. Again a mixture of short and long journeys. My engine seems to be quieter, smooth driving and a bit more power. MPG? Well I don’t know as I never really kept a record of it. I filled up once a month before using D-Max and I still do. I will defiantly purchase again when my next 5000 miles are up.
– kevin
well, I’m amazed with this product I put it in a half a tank of fuel,put £20 in to mix it up then of to a long duel carriage way and ragged the engine and wow what a differential in the performance in my 2ltr Mondeo car it starts fine and the engine runs lovely and smooth I will use this again once a year and every year from now on thanks guys.
– Dave
Worked like magic, power back, fuel consumption is getting better each longish trip… Previous owner six miles each way to work at about 45/50mph… Not good for any engine, it was choked up… And wouldn’t pull the skin off a rice pudding……
Now it’s pulling like a train. THANK you for a brilliant product.. Dave…
– Robin
very nice product
– Robin
Worth for price
– Mark
I used this product followed by the ar6200 I noticed the engine running smother and fuel consumption went up by 3mpg. What I would like to know is does any of the archoil products clean the inlet manifold and the egr valve.
– Terence
“I ordered this last week and received some sound advice from Paul, who was genuinely helpful, giving me a lot of time and attention on the phone.
I’ve used the BG244 in the past for my diesel Lexus IS200 (2009) and it has been fine, it is not a myth and what others have been saying on the site is not just random hype. I RARELY give feedback for products as I buy anywhere online, but the truth has to be said in this case. When the Powerenhancer team said that these fuel treatments are solutions, they are not joking around!
I used the Archoil AR6400-D Diesel Cleaner and AR6300 Fuel Modification Complex for my 2009 Lexus and after a few miles of driving I felt the difference. The sluggish behaviour was gone! I had an issue where the car was pulling back and after the treatment it was gone! I prayed for a solution and this was the answer. I went to the mechanic and he quoted me £300 to clean out a part I can’t even remember the name of. They said that it’s a part the often goes wrong and needs to be either cleaned or replaced – this was obviously not the case. Others should try it out for themselves just like me. I’m surprised these products don’t have a money-back guarantee.
Thank God and thank you Paul for all your help.”
Kind regards, Terence.
– James Murray
“Order received on time – great products, already getting better fuel returns and my car seems a lot smoother now. Going to order more for the other family member’s vehicles. Thanks for advice on products.”
– Mr Brian Sparks
“Just a quick email to congratulate you on the Diesel Fuel Injector Cleaner. It did exactly what it says on the instructions, cured the fault code on my Saab 9-3, tried other ones but to no avail, so will order from time to time this excellent product.”
– Peter Smith
“Hi, thank you for my ordered items and your efficiency in getting them shipped out to me so promptly. I recommend both your company and products to my friends and family, as I have used several of these items for quite a while and have seen (and felt) noticeable performance improvements.”
– Dan
“Thank-you for your recommendation for the fuel additive for my ‘53 plate Volvo S60 D5 with currently 186k on the clock. What a result!
With a bottle of AR6400-D applied to tank, no thump in the back and noticeable power increase, however post treatment it 100% definitely requires less throttle input to pick up revs! Also the classic diesel plume that appears when on boost has all but vanished!?! Incredible!!!
Commute mpg is up already and all of the above has been experienced just after 44 miles! I look forward to further improvements as it continues to clean lube and whatever other wizardry things AR6400-D does. Always been sceptical, but I’m a convert and after covering my next 5k as recommended, I’ll be back for another batch.”
– Asim B
“Hello, I drove to the south of France to visit relatives and they have a string of high mileage diesel cars and vans. I bought a bottle of AR6400-D to use on the trip. However at arriving at the host’s home, the discussion of Diesel engines came up. The conversation ended with me gifting them my bottle of AR6400-D.
Their old Renault Megane diesel with 340,000 km on the clock was completely transformed by your magic potion – they thought the car was on its last legs. Under 100 miles of driving with Archoil in the tank became quieter, faster and more responsive.
My host was so impressed with Archoil, he called his local garage owner at 11pm at night demanding to know why he hadn’t stocked any Archoil.
Good luck, I think you have a new bunch of customers here in south of France. All with diesel cars and fleet vans to operate.”
Thanks.
– Jonathan Kelly
“I’ve never written a testimonial before but your product deserves it! I have a Mondeo 1.8 TDCI which has now covered 132,000 miles and delivers 61 mpg.
On the two occasions that my engine had starting problems: once at 67,000 miles and second time at 88,000 miles I immediately used a bottle of AR6400-D.
Both times it solved it within 2 to 3 days. Since then I have run a bottle through every 10,000 miles with no problems in last 50,000 miles (5 bottles). This fuel additive makes the engine run smoothly too, however you can tell it needs it again after 8,000 miles since last bottle.”
Keep making this!
– J Smith
“Dear Sirs, I have just completed a course of your AR 6400-D and the small bottle of concentrate on my Audi A6 All Road which has now completed 211,000 miles.
This product did exactly what you said it would. I had forgotten how smooth this engine could be and the Emission fault light (which had been on for 20,000 miles) went off after about 300 miles. I wish to continue with your product, so what do you recommend to maintain the continued reduction in carbon etc.”
– Anonymous
The following is an article I posted on the Jaguar forums, if it is of any use to you then please feel free to use it.
“Hi guys. I’m new to these forums however I’ve found them a very interesting read. I’ve had the same problem as most on here with the car showing more warning lights than a jumbo jet out of fuel! Because of the constant selection of ‘Limp’ home mode, one garage said they would have to take the gearbox apart at the cost of a couple of thousand pounds.
A couple of weeks ago the car wouldn’t start at all – after 5 days of scratching my head and after reading these forums I found out about the EGR Valve and someone said tap it with a rubber mallet, which I did. Hey Presto the bloody thing started. It seemed to me that the slightest bit of dirt would make the valve stick and because the sensors really couldn’t tell what was wrong all sorts of lights lit up and ‘limp’ mode engaged.
Anyway, I have solved all my problems with an amazing product called Archoil. The product was AR6400-D. It’s supposed to clean your system including the EGR. I have only had the stuff in there for about 100 miles now and the difference is amazing. I’m hoping that before long I can take the rubber mallet out of my boot! It’s embarrassing sitting in the supermarket car park belting hell out of a Jaguar engine to make it go like most cars – I’m sceptical about products like this but I was desperate and willing to try anything.”
Footnote: I am in no way connected to the makers of Archoil. Just an ordinary Joe trying to get his car to work efficiently.
Thank-you.
– Harry
“Hi David, There’s a link to the AR6400-D thread I just started on thedieslgarage.com. There is no question this stuff (as well as all of Archoil’s products) sets the bar well above all others. Everyone I work with is a believer in these products – and these are master certified technicians with tons of experience, they run Archoil in all of their own personal vehicles.”
– Ian G. Oliver
“I’ve used AR6400-D on my engine to great effect – It seems to have freed up a sticky turbo too! I found it better than BG244, which I’ve used for a few years in that respect.
After using the 6400-D I then discovered the existence of AR6400-CR. Since my engine has common rail injection, please can you tell me if I should have used the CR version of AR6400 and not the D version? Does it make any difference? What is the difference between the AR6400-D and the AR6400-CR please?”
– James
“Hi there, firstly postage and packing – all very quick and prompt. The parcel was very well wrapped, but must have been subject to a bit of a beating as the AR6400 had seeped a little. Didn’t seem to have lost much, so not the end of the world but makes you wonder what had happened to it to make the seal fail!
Anyway, onto the product itself. My car is a Saab 9-3 TiD 150 on a ’07 and was averaging 38 mpg doing motorway miles at about 600 miles a week. I knew something wasn’t right, but so far it’s had the EGR, MAF, MAP and injectors all checked and nothing found to be wrong. The DPF has been regenerated but still the car seemed down on the economy figures and a little ‘flat’. I had been using Millers Eco Diesel Power Plus with every fill-up but I thought it would be worth giving the AR6400 a go after reading about it being a ‘new technology’ (and not simply just a bottle of Kerosene or Two Stroke Oil).
I’ve now done a full tank – the exact same driving I do every week and the mpg is reading 44 mpg – I didn’t modify my driving style and the car is exactly the same but the AR6400 seems to have worked wonders. In addition, it feels smoother too and generally more pleasant to drive thanks to a feeling of more torque being available.
I’d recommend AR6400 to anyone who has checked the items I have, and still feels their car is lacking. It’s not a magic potion and won’t fix a broken car or parts but it’s really done the trick for me! Feel free to use this review – it’s a good product so it’s worth shouting about.”
– Kelly P
“I recently bought your AR6400-D from your website, and only bought my Peugeot 407 HDi 2.0 in January and had just over 105,500 miles on the clock.
The car was giving me about 44.5 mpg. Since putting the AR6400-D in the car, it’s now giving me about 50.0 to 51.5 mpg. The car now runs a lot smoother and has more power WOW!! I’m impressed, once used I will use the AR6200 20ml bottle to treat 200 litres given to me as a sample.”
– Bruce
My 2004 VW Golf V 2.0TDi 150,000 mls was intermittently misfiring – VCDS diagnostics identified injector fault on Cyl.No.4. Added AR6400-D and ran for 50 mls and the fault has cleared ……….. hopefully for good! Re-checked with VCDS and no faults found. Great!
– peter
I have owned a 2013 Toyota Avensis Tourer 2 litre diesel (25000 miles) for10 months and know nothing about cars! However I decided to try the Archroil AR 6400-D Pro Diesel Cleaner.
Before using it my long term average was 53mpg. Since using it I have had two full tank tests returning 58 and 59 mpg. Very pleased. I intend to use it on an annual basis as I average only 10k per annum.