Best Fuel Injector Cleaner

Fuel injection systems, in their essence, involve the rapid opening and closing (actuation) of mini valves which helps to regulate the amount of fuel that goes into a vehicle’s (or motorbike’s) combustion system.

With automobiles, the regular configuration of the majority of vehicle engines sees the engine located extremely close to the intake valves. This proximity means that carbon, oil and heat are all moving in the general vicinity of the intake valves which can cause small amounts of dirt to built up over time. Tiny deposits of residuals from these passing materials can make the fuel injectors extremely dirty, which creates future problems with dirt and grime that prevents the engine from performing at its best. Eventually, this leads to impaired engine performance, or worse, when not managed over time, complete engine failure.


Fuel injector cleaner products are liquid solutions that are poured into the gasoline or diesel tank as a fuel additive. This works are a type of cleaning solution to remove the deposits and clean out dirt that is found to be clogging up the fuel injection system in a vehicle or motorbike.

These types of motor engine products are intended to be used on a regular basis – weekly or monthly depending on the need – in order to maintain the fuel injection system outside of a full vehicle servicing period. It is possible to clean the fuel injection parts too often with some cleaning solutions, so mind needs to be paid to the limits here.

Following extensive testing of a number of different pour-in engine additives to clean clogged fuel injection systems, we have reached our conclusions. Our recommended products are covered in the detailed fuel injector cleaner reviews that follow which assesses with the best fuel injector cleaner, the best fuel injector cleaner for the money, and the best fuel injector clean on a budget.


Best Fuel Injector Cleaner

BG 44K Fuel System Cleaner

Rapidly Cleans Fuel Injectors, Valves and Combustion Chambers


The BG 44K Fuel System Cleaner wins in our Best Fuel Injector Cleaner category.

BG 44K is an 11 ounce pour-in solution that aims to restore overall vehicle performance and improve gas mileage by a noticeable amount. Whether through low quality gasoline or tiny dirty deposits generated through the combustion engine system, this leading liquid cleaner intends to solve this problem by placing the solution in the car owner’s hand.

The formulation of the product makes it easier to clean the complete fuel system rather than only one small part of it. Everything from fuel filters, fuel injectors, ports and intake valves through to the combustion area itself gets the powerful 44K treatment.

Improvements to performance should be noticed following a short 30 minute drive to let the engine hum and the fuel with the poured-in fuel injection cleaner mixed sufficiently. Changes in performance when using the BG 44K product often include a cessation of engine stalls, hesitation, stumbles, and of a sudden power loss at the worst possible time.

The BG 44K mixture works with only gasoline-fueled engines, and so is not suitable for engines designed for use with ethanol and other alternative fuel types. Alternative fuel additives usually can co-mingle with the application of the BG 44K cleaning solution without creating any noticeable issues or engine difficulties but one should pay special attention when doing so.

The recommendation for usage is a single 11 ounce can of BG 44K for every 10,000 miles traveled or used once a year for cars or bikes that are not driven very often. Only one 11 ounce can is required to mix with a twenty gallon tank to get the mixture right during application. Therefore, it is necessary to be reasonably sure about the amount of gasoline left in the tank before applying the BG 44K mixture to ensure the proper levels are used. Using too much or too little of the cleaning solution could have a detrimental effect on future vehicle performance, so it’s important to pay attention to this detail.

BG 44K Fuel System Cleaner has been the recommended fuel injection cleaning solution of choice for working mechanics over a four decade period of time. Many mechanics swear by its effectiveness and use it in their own vehicles when outside of a regular service period.


Best Fuel Injector Cleaner for the money

The Red Line 60103 Complete SI-1 Fuel System Cleaner wins in the Best Fuel Injector for the money category.

Red Line (60103) Complete SI-1 Fuel System Cleaner

Cleans to nearly 100 percent efficiency in one treatment

The owner of the vehicle has the choice whether to purchase the product as a single cleaner or in a 12-pack which allows vehicle owners to save money on a bulk purchase. The individual bottles contain 15 flow ounces of cleaning solution. Motorbike owners can purchase a smaller 4-ounce dosage which is the exact same cleaning solution just in a smaller size.

The Red Line 60103 Complete SI-1 is capable of cleaning dirty deposits from fuel injectors, valves, carburetors and the combustion chamber. This product is also perfectly able to clean pollution control valves too, which is handy.

The cleaning solution itself uses a highly concentrated mix of low temperature and high temperature detergents, which includes a synthetic lubricant for the upper cylinder too.

The full 15 ounce bottle is capable of treating 100 gallons of gasoline or oxygenated fuel sources. The appropriate application of this pour-in liquid cleaner has a near 100% cleaning record which makes it highly efficient. It also cuts the requirement for octane by as much as two points. With a vehicle that has been neglected and left for a long period of time, it is recommended that a single 15 oz. bottle should be used per gas tank for cars that haven’t been serviced in years. The cleaning solution has been created to be safe to use on a regular basis to clean the fuel injection and related fuel systems effectively.

The Red Line SI-1 has been cleared for use on many classic and high performance vehicles from SVT Cobra to Mustangs from 1977 to 2016, to Shelby GT 500 to the Mach 1.

This product is mostly intended for use with gasoline-fueled engines rather than diesel-fueled or ethanol-fueled ones. It has a higher than normal concentration of polyether amines (PEA) which is the most common cleaning ingredient used in the majority of engine cleaners today. However, it does not offer the same kind of lubrication qualities that some other fuel injection cleaners do. For this reason, a separate lubricant is recommended for use when opting for the cleaning strength of this Red Line product.


Best Fuel Injector Cleaner on a budget

The Lucas 10003 Upper Cylinder Lubrication & Injector Cleaner is the winner in the Best Fuel Injector Cleaner on a budget category.

Lucas 10003 Upper Cylinder Lubrication & Injector Cleaner

Automotive Oil & Gas Treatments

This type of cleaner is formulated to neutralize sulfur-related fuel issues and clean the complete fuel system from the fuel injector to the intake valves and everything in between. Unlike the other two fuel & engine system cleaners, this budget solution, which comes in a 32 flow ounce bottle, can clean both diesel and gasoline engines, whether they are fuel injected or carburetted. The gasoline can also be leaded and use of the Lucas 10003 cleaner also helps to improve the gasoline octane rating too.

The blended cleaning solution is a potent detergent that mixes additives and slick oils which helps both clean the engine and lubricate it at the same time. Because of its ability to clean the fuel injectors and lubricate the carburetor, the fuel system and engine will perform more smoothly after its thorough application, using less fuel in the future with a greater power output to boot. The pumps and fuel injectors also get an extended life when using this affordable Lucas 10003 Cleaning solution.

Beyond regular commuter vehicles, this cleaner can also be used on marine, locomotive and non-road diesel engines which puts it in a class of its own within the 3 recommended products in this review.

This cleaning solution doesn’t contain any solvents, kerosene, alcohol, diesel fuel or other corrosive component that could cause any damage to engine parts.

For vehicles that are able to use leaded fuel, the removal of contaminants helps mitigate the negatives associated with the use of this type of fuel. Similarly, when using a diesel engine, low sulfur diesel fuel can be harmful and the use of this cleaning solution resolves the issue too.

Exhaust fumes are cleaned up when having used the Lucas cleaning product which helps vehicles pass their emissions standards testing requirements.

The recommended fuel treatment with this pour-in fuel additive is 2-3 ounces for every 10 gallons of fuel present in the tank. This makes the 32 ounce bottle of Lucas 10003 Upper Cylinder Lubrication & Injector Cleaner excellent value. This is greatly emphasized by the lubrication aspects of the product as well. With that said, the cleaning potency is not as strong as with either of the more expensive recommended products reviewed.

Why you need a Fuel Injector Cleaner

A cleaner for the fuel injection system is a necessary part of personal maintenance of a vehicle (or motorbike). Whilst during a major servicing, it is possible for the servicing mechanic to perform a complete overhaul and a cleaning of the fuel system within the vehicle, yet this is quite unusual.

fuel_injector-cleaningThe performance of the engine and the fuel injection system between servicing periods comes down to the owner of the vehicle performing their own timely maintenance. This avoids a situation where the car performs best right after a service, but slowly suffers from poorer performance as the time moves away from when the last service appointment was completed.

One area that can be easily handled without the need for advanced vehicle knowledge is with the fuel system. The process of ongoing vehicle use, low quality gasoline, dirty gasoline pump stations, and other contaminants all conspire to leave dirty deposits on the intake ports, fuel injectors, and inside combustion chambers and intake valves.

The effect of these dirty deposits that collect over time includes engine stutter, engine stalling out, lower fuel efficiency, dirtier exhaust emissions, and detrimental drive-ability. A recommended liquid solution for cleaning fuel systems can simply be poured into the gasoline tank, matching an appropriate gasoline tank level with the correct amount of cleaning solution, in order to help the engine clean up the fuel system during the next drive around town.

The fuel injection liquid can be applied every 10,000 miles driven or every years while following the instructions for the cleaner product precisely. Do bear in mind that each fuel injector cleaning solution works a little differently and therefore only use the instructions for the selected product, rather than heresay from a well meaning friend whose used a similar, but not identical, product before.

What makes a great Fuel Injector Cleaner – Buyer’s Guide

Each fuel injection cleaning solution is different. It is useful to pick the one that suits your vehicle the best. For instance, the BG 44K product is only to be used on gasoline engines, so an engine that requires ethanol, diesel or another alternative fuel source won’t be acceptable and could damage the fuel system when used incorrectly.

In most cases, a fuel injection cleaner will be able to clean not only the fuel injectors alone, but also other parts of the fuel system like the intake valves, the intake ports, and the combustion chambers. No one area is immune from the nasty built up of dirty deposits that can seriously affect vehicle performance in the future.


A good fuel injector cleaner ideally has a strong reputation built up over many years. Our best fuel injector, the BG 44K Fuel System Cleaner, is backed by over 40 years of happy mechanics who have found the product useful. This kind of long-term experience speaks volumes about the power of the product and its ability to clean up most gasoline-based fuel systems effectively. This is certainly something to look out for when comparing an established product to a new entrant with little to recommend it other than some flashy advertising that initially catches the eye.

The manufacturer of the fuel injection cleaner should provide clear, concise instructions for vehicle owners who wish to apply the pour-in liquid cleaner in an appropriate measurement, without either needing to be a mechanic or perform some advanced mathematics to add the correct amount of liquid correctly. Products with unclear instructions aren’t likely to sell well or get many satisfied customers.


The time it takes for the fuel system to be cleaned following the application of the liquid cleaner varies from product to product. With that said, in most cases, a short drive around the neighborhood should be sufficient to at least begin the cleaning process. These fuel injector cleaners are never intended to be slow acting products. With that said, the strength of the solution is also a key factor because one doesn’t want to go through cases of cleaner solution to keep the fuel system clean over time.

Less expensive alternative products may look good because they shave a few dollars off the price of the well reviewed cleaning product, but mostly likely what they shave off in price, is an indication of a weaker product that requires more solution to create a similar cleaning result. There is also the fact that it is not smart to use a fuel injection cleaning solution from an unknown provider because there is the risk that it could do more damage than good; pay the appropriate price and stick to the trusted names with many years of experience in the automotive industry.


Best Fuel Injector Cleaner – Full Review

The BG 44K Fuel System Cleaner is the overall winner for Best Fuel Injector Cleaner.

The BG 44K package is an 11 ounce cleaning solution that is applied by pouring it into the gasoline tank in the required amount. The appropriate amount of cleaning solution depends on how full the gasoline tank was at the time rather than how much cleaning fluid the driver wishes to use. Consult the packaging to confirm the correct ratio with the latest formulation of BG 44K.

BG 44K Fuel System Cleaner

Rapidly Cleans Fuel Injectors, Valves and Combustion Chambers

619cawuMHcL._SL1500_This cleaning solution is intended to clean dirty deposits that collect within the fuel filters, ports, fuel injectors, intake valves, and the combustion chambers which comprise the complete fuel system of a vehicle. The process of fuel injection opens and closes valves thousands of times in a single journey and dirty residue can be deposited over time which effectively clogs up the works. Unclean fuel pumps at gas stations and dirty fuel sources can also create problems for the engine and fuel system with a vehicle later on.

The BG 44K Fuel System Cleaner was formulated over 40 years ago to help deal with such issues in a manner that doesn’t require a qualified mechanic to take the action for the car owner. Busy mechanics have been applying this product to serviced vehicles for decades. Many mechanics swear by its effectiveness in resolving troubling engine rumblings, a lower engine performance than expected, and problems surrounding fuel exhaust emission issues.

The fuel injection system can be looked at during regular servicing. The BG 44K cleaning solution has been found to be the most effective at cleaning dirty fuel systems. It also has a lubricating effect on the engine which is helpful too.

Only gasoline engines and fuel systems can be cleaned using this product. Engines that use diesel and other forms of vehicle fuel cannot accept this product. It would be dangerous and potentially damaging to the engine to use this fuel cleaner on a non-gasoline engine.

One 11 ounce can of BG 44L is enough to treat a vehicle every 10,000 miles driven or every year when a vehicle hasn’t been driven very often. The use of this product is not solely determined by miles driven as dirt can get built up over time, even without extended use of the car during the year.

The fuel consumption can be improved, sometimes by as much as 20 percent, when regularly using this product. This has to be measured by the individual driver and compared to the cost of this product which is not particularly expensive. In most cases, the car owner is likely to come out ahead when they drive a reasonable number of miles each month to/from work and on trips on the weekend.


Following the correct application of the BG 44K Fuel System Cleaner, motorists will find that driving around the block will not be enough to satisfy the requirements to clean the engine, fuel injection and related fuel systems. In many cases, the longer the trip, the better to get the most out of this potent cleaner. Drivers tend to discover improved power and a new agility to an older vehicle that seemed to have lost its punch long ago, but has found a new lease of life following the use of this product.

It is important not to overuse the BG 44K cleaning solution in a single application. This is because it is possible it could cause problems for other components like filters or a catalytic converter. Typically, there are no negative outcomes when choosing to clean the fuel system on a monthly basis – some drivers choose to do this – yet only the “road warriors” who rack up thousands of miles on the road every month should consider this option.

Unclean fuel pumps at gas stations and dirty fuel sources can also create problems for the engine and fuel system with a vehicle later on.

The liquid is corrosive on paint surfaces, so a plastic funnel should be used to carefully route the cleaning solution into the gasoline tank (be sure to take the vehicle’s gasoline cap off first to avoid accidental spillage).

In our tests, BG 44K Fuel System Cleaner provided the most convincing results. It is fair to say that this cleaner will only clean gasoline-fueled engines and fuel systems, whereas other cleaning products can do more, but what it does, it does particularly well. It also has an extremely long pedigree of over 40 years of use by generations of mechanics, which is something that just cannot be discounted either. The cleaning formulation is particularly strong – not the strongest, but strong enough – to do a good job. It’s pricing is also typically pretty competitive compared to the alternatives available. Overall, for anyone driving a gasoline-fueled vehicle, they cannot do better than the BG 44K cleaning product.

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Best Fuel Injector Cleaner for the money

The Red Line 60103 Complete SI-1 Fuel System Cleaner is the overall winner for the Best Fuel Injector Cleaner for the money. What does this actually mean? It means that based on the value of the product and its price, it delivers the most bang for the buck. It’s neither the most expensive cleaning product or the most affordable one either, but it hits the target being somewhere in the middle which is fine with us.

Red Line (60103) Complete SI-1 Fuel System Cleaner

Cleans to nearly 100 percent efficiency in one treatment

What stands out right away with the Red Line 60103 SI-1 Fuel System Cleaner is that it uses more polyether amines (PEA) as its main go to cleaner component than the other two winning cleaning solutions. This is actually true across many other cleaning products; this one is pretty strong for an over-the-counter cleaning option. And that’s certainly not a bad thing, especially for any vehicle owners with an old vehicle that hasn’t been touched in some months (or years) which really needs a good clean out of its engine and fuel system while wanting to avoid the need to pay for a costing servicing bill.

71Fkr3hxDOL._SL1500_This cleaning solution cleans everything from the combustion chamber to the fuel injectors and also the carburetor too. Even the pollution control valves get the spring cleaning treatment. This is because the cleaner is a concentrated mix of detergents that are efficient cleaners at low and high temperature environments. As such, there is an almost 100 percent efficiency for each single treatment which can give buyers some confidence.

The cleaning solution bottle is actually 15 flow ounces, but it is possible to only use 3 ounces for a typical full tank of fuel. Buyers will need to check the exact measurements of what is suitable for different fuel tank levels, but the strength of the cleaning solution is demonstrated in how little needs to be used to get the desired result. A single bottle can treat up to 100 gallons of gasoline or oxygenated fuel, with only long neglected vehicles having a possible need to use the entire bottle in a single treatment.

For anyone who owns a high performance vehicle, this Red Line product could well be the right one. Whether owning a Mustang from 1979 to 2016, a BOSS, SVT Cobra or a Shelby GT 500, this solution is tested on these models and will be suitable. Obviously, for drivers who own a different high performance sports car, verify whether it will be suitable, or not, before applying the solution to the fuel tank. Never make an assumption that it’ll be correct, because applying the cleaning fluid to the wrong vehicle type could be seriously damaging to the engine and fuel injection apparatus.

This Red Line SI-1 product doesn’t just clean the fuel system and the engine, it also lubricates them too. This helps to ensure the smooth running of the vehicle once it has been cleaned. It is also quite frugal because it saves having to purchase a separate engine cleaner too. With a cleaned and lubricated vehicle, the engine can fire on all cylinders more efficiently, less fuel is consumed, and the exhaust emissions are not as harmful. That’s a fair amount of progress for a single cleaning product.


This product is not recommended for diesel-fueled engines under most circumstances; principally it is intended for gasoline-fueled engines. Other engine types like LPG-fueled engines are also not suitable.

The Red Line 60103 Complete SI-1 Fuel System Cleaner manages to strike a nice balance between cleaning ability, lubrication and value for money. The formulation of this fuel injection cleaner is strong enough with more PEA used than most other cleaners to cut through more dirt and grime built up inside engines and fuel injection parts. The added lubrication to these same parts of the vehicle without needing to use a separate lubrication product is a nice extra. As such, this product provides a good amount of value outside of looking purely at its purchase price. The product has also been available in the marketplace for a number of years and is a trusted solution by many drivers who’ve often found that its stronger formulation to be its most useful feature.

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Best Fuel Injector Cleaner on a budget

The Lucas 10003 Upper Cylinder Lubrication & Injector Cleaner is our winner of the Best Fuel Injector Cleaner on a budget category. In fact, even if this product hadn’t won in the affordability category, it may have won one of the other two categories because it offers so much value to vehicle owners.

Lucas 10003 Upper Cylinder Lubrication & Injector Cleaner

Automotive Oil & Gas Treatments

Unlike the Red Line 60103 Complete SI-1 Fuel System Cleaner and the BG 44K Fuel System Cleaner, the Lucas 10003 injection cleaner aims squarely at the fuel-injection market and targets multiple types of engines. This cleaner not only cleans gasoline-fueled engines (leaded and unleaded fuel), but it also cleans diesel-fueled engines too. Both fuel-injected and carburetted engines are actually supported. Not only that, but it goes several steps further by being able to be used to clean other diesel-fueled engines used in Locomotion, Marine, and even non-road engine types.

710buWUpkOL._SL1500_A 2-3 ounce pour-in fuel additive is all that’s needed to treat 10 gallons of fuel (gasoline or diesel). The product’s sold in 32 flow ounce containers, which is enough for several treatment cycles. Whilst care should always be taken not to exceed the recommended dosage per the gallons of fuel located in the fuel tank, it is believed that this Lucas 10003 Upper Cylinder Lubrication & Injector Cleaner is not harmful to engines when too much cleaning solution is added by mistake. For less experienced vehicle owners who are not used to conducting vehicle maintenance themselves, this may be a welcome little extra.

For families running multiple vehicles some of which are gasoline-fueled and some of which are diesel-fueled, this product may not only be the cheaper choice compared to the alternatives, but could be their one stop solution for all their engine and fuel injector cleaning needs. This makes the Red Line cleaning product an attractive proposition for any family looking for more simplicity within their vehicle maintenance program.

The improvements to gasoline engine functionality helps boost the octane rating by a couple of points. With a cleaner engine and fuel injection system, vehicles often discover a sudden boost to their available power under the pedal and in many cases, enjoy modestly increased fuel mileage too. With the cleaned up system, dirty exhaust emissions that would have failed vehicle safe emissions tests are likely to now fall within acceptable emission limits. Fewer contaminants helps mitigate the negatives with using leaded fuel and diesel also becomes clean enough to use low sulfur diesel fuel without its damaging effects.


Lubrication is a large part of the attraction of this cleaner. Once the cleaning process has been completed, the lubrication helps fuel become slicker moving more easily to the cylinder walls and around rings which helps to extend the life of the vehicle parts. In fact, the entire fuel injection system gets lubricated from the fuel injectors to the intake valves which ensures the vehicle will keep humming along comfortably in the future.

With reduced wear and tear on vehicle parts due to better lubrication, damage due to corrosion or excessive friction is considerably reduced. This means that servicing will be less costly and require less time than it otherwise would have done due to original component parts lasting longer. This has the added benefit of not needing to car pool or pay for a hire care while the vehicle is being repaired.

The Lucas 10003 Upper Cylinder Lubrication & Injector Cleaner is an impressive product that does even better in our estimation because of its lower price. Whilst it may not be the best lubrication solution on the market, it does pretty well with its engine and fuel injection cleaning abilities. Being a solution that can be used in both diesel-fueled and gasoline-fueled vehicles really is the icing on the cake here. The product offers exceptional value in the budget category for vehicle owners who are either frugal or needing to trim their vehicle maintenance costs down.

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Other Considerations

One way to compare competing fuel injection cleaning solutions is to look at the level of polyether amines (PEA) listed for the product. This is the main active cleaning agent used in the vast majority of fuel injection over-the-counter cleaning products. Vehicle owners can therefore choose simply to go with the product with the highest level of PEA.

On the other hand, some products include lubrication which can help the engine perform better over time. Rather than needing to buy a separate engine lubricant, it is sometimes possible to make a two-in-one purchase of a single cleaning product that can perform a dual role for the owner of the vehicle.

71Fkr3hxDOL._SL1500_Consider the value of sticking to brands that have been involved in the successful manufacturer and distribution of fuel injection cleaners for years, perhaps even decades. When it comes to applying a fuel additive to clean the vehicle’s engine and fuel injection system, focusing entirely on the dollar cost of each product is probably not the best way to go, all other things being equal.

Depending on the cleaning solution, some are only intended for gasoline engines, whereas others can be used in diesel engines too. Furthermore, a few cleaners are even more flexible and can be used on non-automotive diesel engines, like locomotive diesel engines.

For families that own both gasoline-based and diesel-based vehicles, they may want to consider buying a single fuel injector cleaner solution that will be suitable for all their vehicles rather than buying one for their gasoline-fueled vehicles and another cleaning product for the diesel-fueled vehicles. Buying separately for each fuel type is too much of a pain to keep up with, especially with a cleaning solution where it is advisable to use it on a semi-regular basis. Keep it simple.

The purchase of a plastic funnel is a good idea as some cleaning solutions are strong enough to be corrosive to paint and metal. It may also be a good idea to wear gloves when handling a fuel injection cleaning bottle to avoid getting any liquid spilled on the hands or fingers, which could create a burning sensation.

Fuel filters do not get cleaned by using a fuel injection cleaner, contrary to what some vehicle owners may believe. Fuel filters simply need to be replaced when the time comes. Occasionally, a fuel injection problem cannot be fixed by using a fuel injection cleaning solution because one or more fuel injection-related parts are actually damaged or broken. In this situation, a mechanic will need to diagnose the problem, order parts and replace the damaged ones to get the fuel injection system working properly again.

A fuel injection cleaning system is not a cure-all solution, but it can still help a surprising amount nonetheless.

Using a fuel injector cleaner is an important part of any vehicle maintenance when outside of the servicing period. It helps to keep the engine and fuel injection system in a cleaner condition to avoid engine misfires, damaging exhaust emissions, and problems arising from a dirty fuel system. The cost of adding fuel injection cleaning fluid to regular vehicle maintenance is pretty minor. It is important to use a fuel injection cleaner on a semi-regular basis, as laid out by the manufacturer of the pour-in fuel additive, to get the best out of the vehicle that’s already been purchased. Using a fuel injector cleaner product is an easy win for car (or motorbike) owners.