Archoil AR6900-D MAX Advanced Diesel Additive Concentrate - 1 Litre | Super Diesel Fuel Converter - Cetane Booster, Injector Cleaner, DPF & EGR Treatment - Treats 1,000 Litres of Fuel

Excellent additive, been using Red x diesel in every tank since I bought my car, was recommended to by dealer. Was an ex demo SUV, had car 10 years, 2.2d turbo intercooler, 178PS , usually get 48 mpg per tank, car can do 0.60 mph in 9.9 seconds though rarely have I attempted that!! lol Keep car serviced annually as per manufacturers service schedule. Kerb weight is 1700kg without driver, a fairly heavy car, performance & economy has always been outstanding, in my opinion, hence decided to keep this car until it starts costing too much for servicing. As Red x seems too expensive now, thought I'd try something else, read reviews on here, and decided upon Archoil AR6900-D and I'm not disappointed. Archoil AR6900-D is exceptional, in my opinion, whilst I wasn't looking for more performance, I've got it, feel like I've suddenly got a sports car. For my car it worked instantly, been overtaking everything in sight. So easy to use, was going on a 200 mile journey, so thought a good test for this. So simple and easy to measure via a cap within a cap, I.E., the outer cap unscrews which is essentially a cover for a nozzle, pour it in then add fuel like I used to do with Red X. As this is my first use of this over a fairly decent journey, I'm ditching Red X, that's for sure, I used more fuel, as was enjoying the overtaking and acceleration so much. The journeys economy dropped to 45 mpg, still acceptable to me, as enjoyed the extra performance, and the engine feels more smooth and quieter. As some other respondents have mentioned, starting a diesel can be an issue, that's been the only downside of this car, it's never liked starting from cold, always starts first time after engine warmed up, had similar issue on all previous diesels, though not as bad as this one. Usually takes at least 2 attempts in summer, 3-4 in winter. Was same when new, was informed about this by the dealer, have to let car idle for 5 mins also before driving also to allow oil to lubricate the turbo, have started from cold several times since adding Archoil, and it starts first time every time. As of writing this in UK in July 2026 it is hotter than usual for us in south England, and it did used to start better when hot outside, but it has never started first time before. The real test will be winter, but any improvement will be helpful. Rather than needing a new costly battery every 2 years, if this helps starting as much has it has already, I'll be saving loads of money, it's also possible this additive may even extend the life of the car.

The short version: Archoil AR6900 has noticeably improved the DPF regeneration process on our high-mileage Nissan Qashqai 1.5 dCi. The longer version: After more than 40 years as a car enthusiast, I’ve tried plenty of so-called miracle additives — many of which turned out to be little more than snake oil for tired diesels. So I approached this one with a fair degree of scepticism. We bought a used Nissan Qashqai 1.5 dCi with over 155,000 miles on it. It had been meticulously maintained, but we knew that using it mainly for short journeys (under 10 miles) would likely lead to soot build-up in the DPF. I monitor the regeneration process using an app, and the miles between regens were quite low. Although the car was completing regenerations (no failed attempts), temperatures rarely exceeded 600°C and soot levels would only drop to around 3–4g — never fully clearing. We started adding AR6900 at roughly 50–60ml per 50 litres of good-quality diesel. I’d also take it for a proper drive once a fortnight to ensure the regeneration process was triggered whilst monitoring it. After the fifth treatment, I noticed a clear change: significantly more miles between regens, regen temperatures increasing to around 650–670°C, and — for the first time — soot levels dropping to 0g. That had simply never happened before. I don’t monitor MPG closely, so I can’t comment on fuel economy, but in terms of DPF performance there has been a definite improvement. From a cost perspective, it also makes sense. Even allowing for the additive, it still works out cheaper than regularly filling up with premium diesel that claims to contain similar detergents and cleaning agents. For me, it’s a more cost-effective way of achieving comparable — if not better — results. I’ve since started using it in a 23-year-old diesel as well and have already noticed smoother running after just a couple of partial fill-ups.

Got my Skoda 2.0 TDI with 12k miles about 8 years ago. I've added a (generous) dose of this virtually every time I fill the tank. With 112k miles on the clock my car is still running well. Engine sounds smooth and quiet for a diesel. I don't know how much, if any mpg it's adding, or if it's actually doing any good. All I can say is that my car starts without any problem on original glow plugs, I get around 50mpg average (70+ on a long, steady run), and no EGR/DPF problems so far. Also, it feels like I'm still getting all of the claimed 150 bhp. It appears I'm on my 5th bottle of this additive, so I've spent a bit over £100. It seems to be money well spent.

Read a few reviews on this product, had big turbo, fuel, and DPF, issues on my 2L deisel TT, bought a Fiesta as a lot on, this product cleans, improves millage, start/stop, DPF issues, whilst using cheaper options of fuel, as a student I really needed this, not sorry I bought, great value for money, will definitely buy again 😀 xx

Have used this in two cars with Egr valve problems and it has sorted within a matter of 200 miles. Both cars run smoother and smell sweeter even for diesels. Can recommend.

I've yet to see the cleaning power as i'm not testing it and comparing before and after in my diesel car but the improved starting capacity has been noticed as I used about 30ml whilst on about 35 ltrs of diesel in a 50ltr tank. I will check my egr in a week or two to see how much it's helped keep that clean as I disconnected my egr to partially clean it whilst in place just before using this product. For the price you get more than one use worth, you get quite a few so this is a product to last over a year depending so for maintaining the fuel and helping the system it's well worth the money. I'm already seeing an improvement to my average MPG which while pottering about town doing short trips is very beneficial. EDIT: After 7 months of use doing a lot of short journeys I can say without a doubt this is a perfect product for keeping a diesel in optimal health as my system runs better, it's cleaner and i'm never having issues with starting, my average mpg has risen to 31mpg which is a huge improvement over the 22mpg I was seeing before I started using it, and if i go on a longer journey it continues to rise until im back to my working day routine doing short trips, and if i take my car out on the NSL roads i'm seeing upwards of 36mpg - did i mention that cold starts aren't an issue anymore? The engine runs so much better with this product in it with the correct amount ie 1:1000 ratio so 1 ltr=1ml, for my 53 ltr tank i need two squirts of this bad boy as they are about 25ml each. I swear by this product as i've had concerns about my dpf and egr getting clogged and being at risk due to my driving habits and after having my egr out twice over the last 7 months to inspect it i can confirm this product is actively cleaning the system, it's not making the egr spotless but the buildup of carbon has been drastically reduced and the EGR is less like a carbon-geode cracked open, even my egr valve solenoid is relatively clean. I'll be forever buying this and adding 70ml to every tank before i top up with new fuel, it's a incredibly affordable product that works like a charm! Please do wear gloves when handling the bottle as while it's not the worst smell in the world you don't want it getting on your hands and then on the interior of your car where you will smell it for weeks.

It definitely has helped my fuel milage has increased and engine sounds smoother, will definitely be getting more.

I had to reduce my star rating to 3 stars because these bottles leak very easily, I put mine in a sealed container thank the lucky stars, But it still stank my car out and took weeks to clear, make sure you keep this upright and in a sealed container of some description otherwise you could have a very bad day indeed.