Posted 20 hours ago

Redex Diesel Fuel System Cleaner 250ml

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But the one question we’ve had from a number of readers since we first started using it is: Can using Redex damage my car? When we did an interim report on the Redex test last month, we said that two out of the three regular users of the car thought it was running smoother, although one couldn’t notice any difference. We’ve been using Redex Diesel System Cleaner in our 100k mile Ford C-Max for a few months to see if it improves performance and economy. Does it work? We had no hesitation in trying this out, especially as just about everyone at Cars UK Towers has used Redex at one time or another, and were confident it was safe to use.

It’s a valid question as you’re shoving additives in to your fuel tank, but the fact is that Redex have been delivering their products for almost 100 years, and are happy to declare that “Redex products will never cause any damage or impairment to your car”, and will do nothing more than provide a “reliable engine-cleaning solution” for users. Which is reassuring. Since May, I’ve been recording my fuel economy every time I fill up the tank – manually noting down the litres added and mileage covered, rather than relying on the car’s trip computer – and adding a dose of Redex to the tank. Thankfully, now we’re finished, we no longer have a hung jury, with all three saying the C-Max is now noticeably smoother, especially when it, or the weather, is cold. The initial baseline figure of 30mpg is pretty indicative of my usual fuel economy result, although usually that’s relying on the car’s trip computer reading rather than direct measurement. After the initial 500mL dose of Redex Advanced 5-in-1 system cleaner, I have been adding a small 90mL bottle of Redex petrol system cleaner every time I have filled up my fuel tank for three months. In my situation, I don’t think I really need to keep using the additives at that rate in my car. I am likely to add a 90mL bottle every month or so and probably use the concentrated cleaner every six months to keep the Mazda’s fuel system sparkling clean. If I had an older car (or when this one starts getting older and higher-mileage), I’d keep using it every tank or at least every other tank.As I outlined in previous reports, the type of fuel additive that I’ve been using is a fuel system cleaner rather than an octanebooster. The goal isn’t to turn regular unleaded into premium unleaded by increasing the car’s octane number, but simplyto give all the tiny pipes and injectors a thorough clean so they can do their thing without being clogged up. Also, if your tank is larger or smaller than 50 litres you can still use the recommended dosage with same level of performance being achieved. My fuel economy figures haven’t shown any changes that could really be attributed to the Redex products. The variation of 3-4mpg above or below the average based on driving conditions and traffic outweighs any potential gain from the products. Again, if you were running a laboratory experiment that directly measured fuel consumption and removed all other variables then you may be able to show an improvement, but it’s nothing really noticeable.

But as 5p a litre is about half the extra of ‘Premium’ fuel, it’s pretty cost-effective as a way of getting your fuel system to work more effectively. Strike three. Will we carry on using Redex?I mentioned in my last report that I’d previously noticed a slight cough or misfire from the Mazda on a couple of occasionsprior to using the Redex products, but hadn’t noticed anything since using the fuel system cleaners. I can report that the engine has still been running cleanly over the last six weeks, so the stuff appears to be doing its job in that respect. Summary

There has been no noticeable difference in performance, and I suspect you’d need a laboratory to really show any improvement. In the variable nature of the real world, and in a well-maintained modern car, I couldn’t detect any difference. Below is a table of my last recording before starting withthe Redex products, followed by one tank of the heavy-duty Redex Advanced 5-in-1 system cleaner and then six tanks using the regular Redex petrol system cleaner. Given that the additives I’ve been using are not performance boosters as such, I wasn’t expecting to feel any noticeable differences to my car’s accelerative qualities. If that was the point, Redex has products like its Petrol Power Booster. Alternatively, I could just fill my tank with premium unleaded fuel, which has a higher octane level than regular unleaded and provides extra power. I’ve just finished a three-month trial of Redex fuel system additives in my Mazda MX-5 to see if I could feel any increase in my car’s performance or measure any significant difference in its fuel economy.

As I’ve made clear previously, this isn’t a laboratory test in controlled conditions but rather a real-world trial that gives a decent indication of what any driver can expect in everyday life. Over about 2,000 miles of mainly commuting in three months, my average fuel consumption using the Redex fuel system cleaners was 31.1mpg. My driving circumstances in that time have been a pretty representative example of my usual activities, so superficially it looks like a 1mpg improvement since using Redex. Given that your engine creates dozens of explosions every single second, there’s a lot of combustion going on under your bonnet. With any burning of fuel, there will be deposits and debris that forms. Sometimes it’s obvious, like the ash that forms when you burn a log in a fireplace. Other times, like in your car’s engine, these deposits are microscopic, but the principle is the same. Over time, these deposits build up and affect your ability to keep burning the fuel properly. The recent cold snap is what convinced our one dissenting voice, as she found the C-Max far less ‘chuggy’ on first start on cold mornings. So strike one for Redex. Has economy improved?

In terms of economy, it’s almost impossible to be absolutely definitive as no two weeks are subject to exactly the same usage, weather or road conditions. Each Redex bottle clearly shows how many shots it contains on the front label, with easy guide ‘shot’ marking on the side. Adding more than one shot of Redex won’t do any harm to your car and can give you a more intensive clean, so don’t worry if your pouring isn’t exact. Yes, we will. But, to be honest, we’ll probably be misers and drop down to using it every other fill-up (which will make it cost just 2.5p per litre of diesel) and see if we notice the C-Max starting to use a bit more fuel, or be less happy when cold. The second week of our test actually saw the mpg deteriorate by 1.5 mpg from the pre-test week, but it’s been a steady improvement since then and we look to be getting about 3mpg more than we did before. It’s not huge – about 6-7 per cent – but we’ll take it. Strike two. How much does it cost to use Redex?Our petrol and diesel fuel system cleaners are supplied in 250ml and 500ml sizes. The smaller 250ml version contains two doses / shots and the 500ml provides 4 shots. One shot of Redex fuel cleaner is capable of treating a fifty-litre fuel tank, but those who have never used a fuel additive before – or those who own an older car – may wish to use two shots for an intensive clean, particularly during first application. It’s also a really easy to use product, just putting a single bottle of Redex cleaner in to the tank at each full-up, which soon becomes second nature. What have we found in the last few months of using Redex? Firstly, if you have an older or higher-mileage car, you are far more likely to see noticeable improvements in performance and fuel economy compared to a newer, lower-mileage vehicle. Given that fuel deposits and debris build up in your engine over time, it makes sense that you’ll notice a greater improvement in an older engine that has seen a few million more fuel explosions than a newer engine. If I’d been running the same test on an older car I am sure I would have seen some more noticeable results, but unfortunately I don’t have an older car to call upon for such a purpose (and buying an old banger to drive for three months didn’t really appeal!) The purpose of the Redex fuel system cleaners is to remove this build-up of deposits and keep the fuel injection system clean. By doing so, the fuel will burn more cleanly and therefore give you better performance and fuel economy as the engine is working more efficiently.

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