What are Fuel Additives & How do they Work?

Rislone Fuel Additives SG AU header 795x287When was the last time you thought about your choice of fuel? Have you ever considered how you can maximize your fuels potential?

Fuel additives allow you to enhance certain aspects of the fuel you put in your car. They can be particularly helpful for old cars, diesel vehicles and driving in specific environments – think cold wet or freezing winter months.

Selecting a fuel additive can be overwhelming, there are so many options so how do you decide which is best for you?

Here is our helpful guide on what fuel additives there are, what they do and how you can get the most out of your fuel.

What Are Fuel Additives?

Fuel additives work with the regular petrol that you buy at the pump, by adding fuel system cleaners, lubricants and performance enhancers to achieve a specific goal. Many fuels have fuel additives in them, but they will never have anywhere near the same performance as a professionally formulated fuel treatment.

Fuel additives work on issues relating to the movement of the fuel or the system it flows through. A fuel treatment with a cleaning agent, will be mixed with fuel to remove heavy deposits, reduce friction and improving the flow of fuel. Components such as fuel injectors and valves need to be free of build up to perform at their peak. Adding a fuel system cleaner can improve sluggish responses ad hard starts. Lubricants work similarly, helping parts to move better and more efficiently. Other fuel additives can prevent gas from freezing in cold temperatures and add performance boosting octane or cetane (for diesels) and keep fuel from going bad over time.

There are a variety of different fuel additives, including those which are designed for off-road or marine use, others may be intended for use in cold or high moisture environments. Most fuel additives are developed for everyday cars with the intention of improving fuel efficiency and performance.

Different Types of Fuel Additives

The benefits of fuel additives vary widely. They could be performance enhancers or fuel stabilizers. Fuel performance enhancers improve the functioning of your fuel. They may do so by cleaning a system and preventing build-up for the future. Fuel stabilizers keep the fuel intact, preventing adverse long-term effects, such as solidification and corrosion. Below are just some of the types of additives you can use in your vehicle.

Fuel Stabilizers

If you’ve got a lawnmower that typically hibernates over the wet months, chances are you’ve experienced the fuel losing its stabilization resulting in spluttering on start up. A fuel stabilizer will help keep fuel from going bad over time. Most fuel stabilizers are intended for vehicles and equipment that sometimes goes long periods of time without being used. Seasonal vehicles, RV’s, lawnmowers, generators and other petrol/diesel powered equipment. The fuel stabilizer improves efficiency and keeps fuel components mixed thoroughly by preventing the separation of the fuel and water. When fuel separates due to being stored for a period, it can cause hard starts, and engine corrosion. If your fuel gets left sitting for a month or so, it is recommended to add a fuel stabilizer, especially if conditions are cold and wet. 

Octane Booster

Before the ’70s, tetraethyl lead, which high in octane, was used as an additive in petrol, that practice ended when we learned of the health hazards of lead. However, high-octane petrol is still sought after by many, it’s association with high power due to its ability to increase the compression ratio. When the compression ratio is higher, there is more air in the engine’s cylinders, which creates a more powerful explosion when the petrol is ignited.

Engines are typically designed to work with petrol at a specific octane level. If a low octane level is experienced, it can cause knocking noise, known as detonation. Detonation is when your fuel explodes erratically instead of smoothly, it is very bad for your engine, as if this occurs over a long period of time it can cause head gasket failure, broken rings, pistons and rod bearing damage. Detonation also causes your engine to run less efficiently. Using ethanol in fuels is one way that petrol refiners increase the octane levels.

Unless your engine is making this knocking sound, you likely won’t need an octane booster. However, some older cars run a high-compression engine, and these types of cars will benefit from octane boosters. Other vehicles that may require an octane booster include premium sports and luxury cars. Octane boosters often include lubricants for the cast-iron valve seats in these older vehicles, these lubricants are important as they help reduce wear on these components and help cool the engine more efficiently.

Diesel Cetane Booster

In a diesel engine, you can increase power with a cetane booster. A higher cetane level causes quicker ignition and better fuel consumption, a short delay between the fuel injection and ignition is a sign of a high cetane level. A long delay is a sign of low cetane levels, which leads to incomplete combustion, more noise and more emissions. With a petrol vehicle, a high-octane level makes the engine ignite slower and more stable, while high cetane level in a diesel makes it ignite quicker. Different vehicles run different optimal levels of cetane. A cetane booster will improve the cetane level in your diesel and improve the fuel efficiency and emissions of your vehicle.

Fuel-Line Antifreeze

In winter condensation can build up in fuel tanks which can result in frozen fuel lines. Some fuel-line antifreeze additives prevent these issues using an alcohol base others disperse the water, absorbing it into the fuel and moving it to the engine, where it safely evaporates into steam and leaves via the exhaust. Ethanol provides some freezing protection, so if your fuel of choice includes ethanol, you will already have some of these benefits. An additive will benefit any vehicle using a fuel that doesn’t contain ethanol, especially diesel vehicles. It is most helpful when temperatures jump from freezing to thawing, as it prevents fuel line condensation caused from the freezing and thawing.

Fuel Injector Cleaners

The fuel injector is electronically controlled and has the important job of spraying fuel into your engine to create just the right mixture of air and fuel for optimal combustion. Pressurised fuel is pushed through the nozzle and sprayed out as an atomized mist, so it combusts easily. When a fuel injector gets clogged it causes stuttering and misfires even during idling, the overall performance of your engine suffers also, resulting in less power and slower acceleration.

A fuel injector cleaner will keep your injectors free of build up and keep your car or truck performing at its best. Some additives are just for preventative maintenance, while others are a little more concentrated and can remove existing carbon build up on injectors and intake valves across a variety of fuel types. They also reduce hydrocarbon, carbon monoxide and nitrogen oxide emissions.

Anti-Gel Diesel Additives

Diesel fuel really can suffer in the colder months. The colder weather causes paraffin wax particles to crystallize in the diesel fuel which clogs both the fuel lines and filters. This severely affects engine performance, and in instances can prevent your vehicle from starting at all, which can lead to major repairs. The diesel fuel combustion process is time sensitive; it depends on certain angles, flow and dispersion. To prevent fuel gelling or crystalizing, this additive brings down the freezing point of the fuel, these products won’t hurt your engine and are most effective if installed prior to the cold weather, however, can be installed after the fact. Many diesel engines, use heated fuel lines to help prevent the gelling process, but it won’t eliminate a hard start like an additive will. 

Ethanol Treatment

Many fuel companies add some ethanol to their petrol mainly because of its availability and ability to reduce carbon monoxide emissions. Ethanol fuel uses renewable sources such as corn, making it an attractive for being eco-friendly. However, ethanol tends to absorb water from the air, making it prone to separation. Older engines often experience higher deposit build up due to not being built for ethanol fuel but having little choice but to use it. An ethanol treatment will benefit these vehicles, by stabilizing the petrol and keeping the engine clean and running at its peak.

Petrol Treatments

A comprehensive petrol treatment can address multiple performance and preventative maintenance aspects. Petrol treatments often remove and prevent carbon build up and use a detergent package to clean parts and stabilise fuel. Some treatments only include one or two of these ingredients and can sometimes be combined with a specialised additive such as an octane boosters.

There are other additives designed for aviation such as antistatic agents, that reduce the static charge build up, to reduce the associated hazards caused by static. This type of additive makes the fuel more conductive and helps prevent the static build up that occurs when fuelling.

A boat, jet ski or other marine craft will benefit from an ethanol petrol treatment, due to being exposed to the marine environment, and the reaction of ethanol petrol to water causing separation, it can cause damage to a marine engine. These additives will stabilize the fuel, improve the water absorption so it stays well mixed together.

What Do Fuel Additives Do?

If you use a high-quality additive for it’s intended purpose, you can typically expect it to provide the results it claims it will. However, additives are not usually a one size fits all, and should be used to address specific issues with compatible vehicles. Using an octane booster on a modern car, may push the octan levels higher than necessary for your engine, and you may not see any benefit in that situation. Similarly, a stabilizer in your daily driver isn’t likely to do much, as the fuel is being consumed more regularly, and won’t require the stabilizing properties, unless you stop driving your car for a month or two. Unless the stabiliser you choose is formulated to cover multiple purposes, it won’t provide the other benefits such as deposit removal or anti-freezing properties.  

Preventative maintenance is a primary use for fuel additives. Keeping you fuel system and injectors clean is one way an additive can improve your vehicles performance. It will help your engine run more efficiently and avoid hard starts and sluggishness. It can help prevent a costly repair due to carbon build up and corrosion.

Some fuel additives need to be installed with every tank of fuel, others can last several thousand kilometres. You should install the additive before you fill your fuel tank up, doing this ensures the additive is dispersed thoroughly into your fuel.

While fuel additives are designed to solve specific problems, there is not harm done by selecting the wrong product, the only thing you must be wary of, is that you don’t overdose your fuel system with any particular additive, as doing so can cause problems to some of the sensors in your system. Always, check the instructions of the additive, and if you are unsure, consult your owner’s manual. Rislone products do not damage your engine, some vehicle manufacturers test Rislone products for compatibility, so you can check with your manufacturer if you are unsure.

Are Fuel Additives Important?

If you want to keep your engine and fuel lines running smoothly for the long term, then yes, a fuel additive can be considered important. Preventative maintenance applies to all aspects of a vehicle, from paintwork to the interior trims, to each engine, gearbox and fuel system component, maintenance will keep your vehicle moving.

Just like keeping your engine free of sludge and providing the correct oil will aid in reducing wear and friction, additional lubrication and cleaning qualities of a fuel additive will help your engine to run cleaner, decrease friction and wear and will reduce hard starts. Even in a premium petrol, there is still room for improvement.

  • Old cars: Fuel additives may be beneficial since these vehicles were produced at a time when petrol and the pump was different, they have different needs to modern cars. Older valve seats, high-compression and older parts that require additives to keep them moving.
  • Seasonal vehicles/equipment: The fuel in the lawnmower or even your boat will go bad if left unused over winter. A fuel stabilizer will help keep it fresh and ready to use when need, this is especially true if you use a ethanol fuel, as this type of fuel reacts strongly to water exposure.
  • Diesel vehicles: Diesel fuel is a completely different composition to petrol and there are vast differences in the design of a diesel engine. Diesel vehicles can benefit immensely from stabilizers, antifreeze and anti-gelling additives.


Additives can solve a wide variety of issues, it is imperative that you don’t mix multiple fuel additives unless you seek recommendation from the additive manufacturer. This makes a multi-functional additive much more attractive to those seeking solutions to multiple issues.  The Rislone range of fuel additives includes a Complete Petrol Fuel System Treatment that delivers a full fuel system clean, including the valves and combustion chamber. It lubricates, removes contaminants and stabilizes the fuel, as well as increasing performance with added octane booster and it treats the system for up to 8,000kms. Rislone Octane Booster, increases the octane rating in your petrol, by up to two rating numbers, it works with all unleaded petrol, ethanol and racing fuels to restore horsepower and stop engine knock and pings.  Rislone Fuel Injector Cleaner, cleans fuel injectors so they can perform at their peak, the Upper Cylinder Lubricant helps prevent cylinder, ring and piston wear, lubricating the valves and guides to extend the life of your engine. The fuel conditioner and treatment, lubricates the fuel system, including the fuel pump, it works with all petrol, ethanol and diesel fuels. For diesel vehicles, our specially formulated Complete Diesel Fuel System Treatment, removes sticky carbon deposits, and provides lubrication to the whole fuel system, with the addition of upper cylinder lubricant, anti-gel and fuel stabilizer it covers all bases and it treats the system for up to 8,000kms.

Start Using Fuel Additives Today

Fuel additives can make a vast difference in your engines performance and life, whether it’s a classic from the 50’s, a brand-new SUV, a 16-wheeler or anything in between. Fuel additives used as part of your regular maintenance, will keep your fuel moving through the system smoothly, and prevent condensation and fuel gelling that prevent your car starting in cold environments.