HYDRA MAXIMUS fuel injector cleaner, 1 Litre treats Up To 500 L, for cleaning diesel injectors performance enhancing diesel turbo cleaner additive for diesel fuel EGR valve cleaner diesel engines

Had a check engine light, obd called it as a a fault on an exhaust sensor, so after clearing the fault code, looked around for a good fuel system cleaner. Amazing stuff, put a couple of doses in half a tank of fuel. Before there was a slight unevenness in the running of the engine and although quick once pushed it lacked that initial urgency. Now it is smooth and more responsive. Not really surprising as it is a 16 year old Mercedes 320cdi, fortunately it is pre-dpf, no EGR and mostly motorway driving which all normally leads to a longer engine life, longer product life and so is why it is running well at 195,000 miles. Overtime, despite full scheduled servicing, the injectors start to block, particularly if you run it down to the bottom of the tank and on some of the supermarket fuels and you see a slight reduction in fuel economy, perhaps around 10%. This can kill a car, my last car had injector problems and often the injector proves impossible to remove as it corrodes into the cylinder head over time and so the car had to be scrapped, as uneconomical to repair. These type of products typically unblock injectors and decarbonise the engine but this one also raises the burn efficiency of the fuel resulting in improved performance and economy. Noticeable difference, definitely would recommend. Will report back later after more use and a longer journey test, but the results from the first two 30 mile outings look promising. Might ditch the detachable filler tube as this makes it easier to keep in the car boot, less likely to smell as more containable. Should make the engine last at least another 200,000 miles countryside and motorway driving. This will keep my internal combustion engine going until we have seen off the EV fad. Just need an additive now to clean the roads of ULEZ. Update, after of a couple of months of use it does not seem to improve fuel economy if your engine is already running running well. Probably this works best on engines that run short journeys and so clog up. Next I will try this on the wife’s diesel..

This additive definitely does something to the car, there is a fuel saving, but not huge, the big thing for me is the result it has on the engine, with the additive the engine is so much quieter and a lot smoother. Running a 110000 diesel Vauxhall so like to look after the engine. I have been using this company's additives for over a year now and rate these over the big name brands 100%

I could feel a slight increase in power and mpg, but the product is difficult to use, once you open it, it has a strong chemical smell and it is impossible to close it back sealed. I would rather buy a single use tube.

Used on a 2007 2.2 Honda Civic i-CTDi. The car always ran pretty smooth due to years of filling up on Shell V-Power diesel. Put this product in with normal diesel and the difference was immediately noticeable. Works out cheaper to buy this and add it to normal diesel than buying premium diesel. Been using this product a few months now after every fill up. Car is more responsive when setting off. Lower revs gives more torque now. BHP has increased when tested. City driving MPG has also gone up by around 8 MPG. The bottle is an awful design and can easily leak. You don't want to keep this product in your home or car though as it is very smelly! The only thing this product DIDN'T do as claimed is clean the EGR Valve. Which was just as filthy as before I started using Maxiumus. Maybe you have to use it for a long long time before it would have any effect on EGR. I will continue to use as it is the best fuel additive I've ever used.

Unfortunately the package arrived damaged and had leaked a little bit - amazon being corteous provided a full refund for this so i essentially got the product for free. My engine is prone to sounding a little bit weird for the first mile or so while the oil heats up, ive always found the engine to run slightly smoother on V-Power but could not justify the £9 per tank extra, it's also not always easy to find a filling station that does V-Power or its equivelant so i started looking for additives. After research i came across Hydra and going by reviews it seemed to be the best offering. I Put the recomended 2ml per L into a fresh full tank of diesel and litteraly the noise that my engine normally eminated during the first few miles has dissapeared completely. I wouldnt say there has been a major performance increase but after a few tanks the car does feel like its got a little bit more response to it and the mpg has went up by about 2 miles. HOWEVER, the DPB-100 from the same brand hydra seems to be an identical product, i think the only difference is the dosing. DPB-100 recomends the first tank at 1ml to 1l of fuel and then 2ml to 3l of fuel as a maintenance dose treating up to 2.5x the amount of fuel and is usually £2-3 cheaper per bottle than the maximus. I think DPB-100 is probably an identical formula with different dosing instructions - its not uncommon for businesses to use this practice. All in all, i think this will be one of the best fuel additives out there, only costs about £2 per full tank and probably provides better results than v-power does - i would highly recomend buying 5l bottles to save even more money. My tank is 60l so i bought 60ml bottles online and have filled them wth this stuff, i keep a couple in my car at all times, this saves the need to use the dosing bottle (which is awful) so takes away the inconvenience of trying to measure out the doses as well as preventing any spilliages or leakages that the dosage bottle is prone to (as i said, mines was delivered with a leak and this stuf STIIIINNKSSS)

Brilliant stuff. Actually does make a difference, after a couple of tanks with this in the engine sounds a lot smoother and feels like it picks up marginally better, it's also much cheaper than buying premium fuel. I've tried many different fuel additives, liqui moly, wynns, stp and a couple of others but this is by far the best.

Quick Background - Car is 2017 VAG 1.6TDi just approaching 30,000 miles most of those previously on Shell V-Power. I don't use the car to get to work anymore and my nearest convenient station is Tesco. Tesco is much cheaper but it just doesn't run the same and is literally a gear different than Shell V-Power on some long climbs near me where I always do exactly the limit (there are cameras everywhere). Anyway, bought some of this (£15 for 500ml) which will treat almost exactly 4 full tanks for me, which is just less than £4 per tank on top of the full tank of Tesco fuel which is *significantly* cheaper than a full tank of V-Power. Filled up and started the test. First thing I would note is that on my car the exhaust fumes when burning V-Power smells like donuts. Burning Tesco diesel smells like diesel fumes. 2 days after dosing I noted that around the back of the car it was the V-Power smell even though I am on a full tank of Tesco (and have been running on it for the last few fill ups now). Second thing:- On cold mornings my car takes longer to start with Tesco diesel. With V-Power I wait for the glow plug light to go out and it fires straight away. With Tesco it can be quite a long crank. With Tesco and Maximus it fires on the first stroke like V-Power, which is what 2EHN is supposed to do. Third thing:- Very subjective but to my mind it's definitely running smoother. Not sure if this is the detergent cleaning the injectors for a better pattern or the 2EHN with the combustion, but all hesitation has gone. Fourth and final thing:- We all know what a car feels like when it's labouring and we change down a gear. I'm consistently using a higher gear than I normally would without knock or labour and if I don't then the car is giving me eco-tips all the time recommending me to change up. I can't give an honest opinion on economy as I'm not really too bothered (it was very good before) but I can't see how it could possibly be worse when I'm consistently driving in a higher gear than what I'm accustomed to. My main reason for doing this was simply that it's now most convenient for me to buy Tesco fuel and they don't do a premium diesel. I wondered if this really would make a fuel better than the "super plus" diesels as Hydra claim, and I'm satisfied now that the answer is yes. The only thing to be aware of here is that most modern cars have a device in the filler neck to stop you misfuelling. If your car has one of those then you need something the same diameter as a forecourt fuelling nozzle else you can't get the Hydra supplied filling tube into the tank neck. On my car with a 60l tank then obviously I can't empty it completely, but on what I term a "full tank" fill up the difference in cost between Tesco and Shell V-Power is at least a tenner (15 if I run very low). The Hyrda Maximus costs 4 quid a dose. But this "feels" better than the V-Power (which I used to use religiously in the past). Would recommend.

I run a 6 year old Renault with the 1.6dci and on the whole it’s a great engine. Since buying the car 6 months ago I’ve changed all the fluids and filters and the car runs perfectly, however I’ve always felt that it was very flat lower in the rev range. Like others I’ve previously used Millers additives in my Diesel cars and can’t say I ever felt much difference so this time I decided to try Hydra’s product - what a difference!! Since adding this at the recommended dosage the car feels noticeably stronger at lower rpm and my mpg has increased by 3mpg on average. I’m now able to drive in higher gears without the engine feeling like it’s labouring all the time and the pickup in any gear feels much better. My engine was always quiet and smooth enough for a diesel, I’d say it’s running a tiny bit quieter and smoother but given my car wasn’t running badly anyway it’s hard to be sure as the difference is so slight - certainly it’s had no negative effect on this at all. Totally agree with the other reviewers, for the price give it a go - it’s not a lot to loose if it doesn’t work for you, but going by my experience a whole lot to gain when it does! I’ll certainly be buying more Maximus going forward. Well done Hydra this is a great product.