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Best Fuel Injector Cleaners

Updated March 2024
Bottom line
Pros
Cons
Best of the Best
Redline Complete SI-1 Fuel System Cleaner, 15 oz.
Redline
Complete SI-1 Fuel System Cleaner, 15 oz.
Check Price
Expert-recommended
Bottom Line

Engine running rough? This product is rated to return your fuel injectors to nearly 100% efficiency in one treatment.

Pros

Red Line cleans fuel injectors, carburetors, valves, and combustion chambers with a blend of high-temp and low-temp detergents. It’s designed to reduce your engine’s need for octane by up to two points, which can save you money at the pump. Contains synthetic upper cylinder lubricant and is safe for continual use on neglected vehicles.

Cons

As with many fuel injector cleanser, some users reported no significant difference after using this product.

Best Bang for the Buck
Lucas 10003 Upper Cylinder Lubrication & Injector Cleaner, 32 oz.
Lucas
10003 Upper Cylinder Lubrication & Injector Cleaner, 32 oz.
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Trusted Brand
Bottom Line

If you’re nervous about passing a smog test, use Lucas Oil to improve your engine’s efficiency.

Pros

A blend of oils, additives, and detergents bring deteriorated gasoline or diesel engines back to life. It also lubricates carburetors and injectors, resulting in fuel mixtures that burn cleaner for more horsepower. Designed to neutralize harmful effects of low-sulfur diesel and replace the need for leaded gasoline.

Cons

Improved power is nice, but this product could potentially increase fuel usage as a consequence.

Royal Purple 18000 Max Atomizer Fuel Injector Cleaner, 6 oz.
Royal Purple
18000 Max Atomizer Fuel Injector Cleaner, 6 oz.
Check Price
Bargain Pick
Bottom Line

A well-priced solution from one of the most reputable brands in the automotive industry.

Pros

Approved for both gasoline and diesel engines, this synthetic fuel injector cleaner stabilizes ethanol, maximizes horsepower, and improves responsiveness. Utilizes highly-concentrated polyether amine detergents to remove clogs and optimizes injector spray patterns. A great fit for those looking to improve idle smoothness.

Cons

Fuel economy gains may not be substantial enough to observe, depending on driving style.

BG 44K Fuel System Cleaner
BG
44K Fuel System Cleaner
Check Price
Alcohol-free
Bottom Line

Cleans and remove deposits from your entire fuel system to prevent engine surges, stalling, hesitation, and power loss.

Pros

One 11-ounce can treats up to 20 gallons of fuel. Thoroughly cleans fuel injectors, intake valves, ports, and combustion chambers for an end-to-end rehabilitation. BG 44K is excellent at restoring old engines by removing carbon deposits, but it can improve performance of newer engines as well. Contains no alcohol and is compatible with all fuel system materials.

Cons

Comes in a can rather than a resealable or closable bottle, which can make storage messy.

Liqui Moly 2007 Jectron Gasoline Fuel Injection Cleaner, 300 ml
Liqui Moly
2007 Jectron Gasoline Fuel Injection Cleaner, 300 ml
Check Price
Simple Yet Solid
Bottom Line

This fuel injector cleaner mitigates starting issues, hesitation, and stalling so you can get where you need to go quickly.

Pros

Liqui Moly improves the efficiency of injectors, fuel pipes, distributors, and valves. The result is cleaner combustion, which leads to better idle quality, improved throttle response, and greater mileage. A fantastic option for engines with catalytic converters, this fuel injection cleaner helps your engine return to its factory performance.

Cons

If you drive a newer vehicle with low miles, you may not see any improvements at all.

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BestReviews spends thousands of hours researching, analyzing, and testing products to recommend the best picks for most consumers. We only make money if you purchase a product through our links, and all opinions about the products are our own. About BestReviews  
BestReviews spends thousands of hours researching, analyzing, and testing products to recommend the best picks for most consumers. We buy all products with our own funds, and we never accept free products from manufacturers.About BestReviews 
HOW WE TESTED

We recommend these products based on an intensive research process that's designed to cut through the noise and find the top products in this space. Guided by experts, we spend hours looking into the factors that matter, to bring you these selections.

38
Models
Considered
190
Consumers
Consulted
16
Hours
Researched
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Buying guide for best fuel injector cleaners 

A fuel injector is one of many key pieces of equipment that’s responsible for how well your car runs in addition to other factors such as tires, batteries and accessories. Fuel injectors deliver a precise amount of atomized fuel at the exact moment needed for efficient combustion. If a fuel injector doesn't function as required, in the long run, it can shorten the life of your engine.

A fuel injector cleaner is a product that helps keep your fuel injector free of debris and buildup. However, not every option is the same. Before deciding which brand is best, you'll need to consider crucial factors, such as whether it’s suited to your type of fuel, how much is needed and how often you need to add it. You'll also want to compare prices and understand how the additives could impact other aspects of how your vehicle runs.

Our favorite is Red Line's Complete SI-1 Fuel System Cleaner, which not only includes high-temperature and low-temperature detergents, but it also enhances fuel stability and can even lower the engine’s gasoline octane requirement. Lucas Oil Fuel Treatment, on the other hand, is the best choice for diesel vehicles.

Best fuel injector cleaners

Red Line Complete SI-1 Fuel System Cleaner

Red Line’s system cleaner immediately stands out from many other options on the market because it has its own patented formula. This fuel additive cleans your entire system, including fuel injectors, carburetors and valve and combustion chamber deposits. It also helps prevent corrosion.

The formula contains a blend of high-temp and low-temp detergents that can reduce the buildup of gummy deposits and varnish formation. This, in turn, can enhance fuel stability, reduce the need for octane by up to two points and help optimize your vehicle's performance. It works best as a preventative measure rather than as a deep cleaner. Just add one 15-ounce bottle to a full tank for the most effective treatment.

Lucas Oil Fuel Treatment

While Lucas Oil Fuel treatment is suitable for use in gasoline engines, it is formulated to be a superior option for diesel fuel. This product cleans and lubricates the entire fuel system, with one bottle being large enough to treat 100 gallons of fuel.

The environmentally friendly detergents and additives in this treatment can help neutralize sulfur and other contaminants that can clog fuel injectors and carburetors and reduce your vehicle's performance. They also prevent rust and corrosion to help extend the life of your engine. Using this product may improve your fuel economy while increasing your vehicle's power and acceleration.

Royal Purple Max-Atomizer Fuel Injector Cleaner

Royal Purple is easily identifiable due to its purple packaging. It is an affordable option that can be used in either gasoline- or diesel-powered vehicles. This unscented cleaner is fully synthetic and formulated with highly concentrated polyether-amine detergents that can clear fuel injectors to restore 100% of the fuel flow.

Using this Max-Atomizer means your injectors’ fuel spray will be better atomized as it enters the combustion chamber to offer you several noticeable benefits, such as easier starts, smoother idling and reduced emissions. This formula also stabilizes ethanol to keep it from breaking down and causing damage to your engine.

BG 44K Fuel System Cleaner

This 11-ounce can of fuel system cleaner can be easily opened and added to your gasoline to clean all of your vehicle's fuel injectors, intake valves, ports and combustion chambers. A single can is suitable for 20 gallons of fuel and removes upper engine deposits to help restore your vehicle's performance and gas mileage.

BG's cleaner is formulated to be compatible with all common fuel additives and alcohol-blended fuels. It works by quickly breaking down common fuel system deposits so gasoline can freely flow throughout your entire system. As a result, it can diminish hesitation and power loss while increasing combustion efficiency and power output.

Liqui Moly Jectron Gasoline Fuel Injection Cleaner

Liqui Moly is an award-winning company that offers a broad range of over 4,000 premium products for vehicles, construction equipment, boats, garden appliances, bikes and commercial vehicles. It manufactures oils, additives and more. Liqui Moly's products are evaluated by an independent German testing firm to ensure they perform as expected.

The fuel injection cleaner is ideal for imports but is also suitable for vehicles manufactured in the U.S. It is safe for older cars, oxygen sensors and catalytic converters. Some of the benefits you might expect after using it include easier starting, smoother idling, decreased hesitation and improved throttle response.

Chevron Techron Concentrate Plus Fuel System Cleaner

Chevron's Techron fuel system cleaner routinely shows up on best-of lists from a variety of sources. The brand’s patented fuel additive technology works to prevent deposit formation within your entire fuel system. If any buildup is present before adding this product, it breaks down those deposits so they can flush through your system, restoring your vehicle to original performance levels.

This fuel-system cleaning concentrate is effective at cleaning both modern and older engines. It is suitable for gasoline-powered vehicles. When used as directed, customers reported such benefits as better gas mileage and smoother running. One other minor, but important consideration is that the product is widely available.

Gumout High Mileage Fuel Injector Cleaner

Gumout has been a trusted fuel additive for over 80 years. The company's long history proves it knows how to manufacture products that consumers like. This potent formula is designed for high-mileage vehicles that have accrued more than 75,000 miles.

It works by breaking down and removing carbon deposits that have built up over the years. The formula is effective on fuel injectors, intake valves and ports. This allows fuel to flow freely throughout your entire system so your engine's performance levels can be elevated. The benefits you may experience include better gas mileage, increased power and reduced emissions.

What are fuel injectors?

Fuel injectors do the same job as carburetors, regulating the mix of fuel and air that enters the combustion chamber of your vehicle. Fuel injectors have become so popular because they do the job more precisely. For you, that means comparative savings on gas or diesel fuel and improved vehicle performance.

Why you need a fuel injector cleaner

Fuel injectors are finely tuned devices with narrow inlets and outlets. All fuel has some contaminants, which is why you have filters in your tank, fuel lines, and at the entrance to the injectors. These filters catch many of the microscopic particles, but a few still get through. The particles might be small, but they stick and accumulate. These particles from contaminated fuel can upset the high-pressure spray created by the fuel injectors.

That's not all. Gasoline and diesel both deposit a carbon residue. Tiny amounts, perhaps, but it builds up. This is seldom a problem in fuel lines, but over time the fuel injectors start to suffer and atomization is affected.

  • Too thin a fuel/air mix starves your engine.
  • Too rich a fuel/air mix makes your engine smoke. 

Fuel injector problems can lead to the following:

  • Poor starting in the cold
  • Misfiring engine
  • Shuddering and knocking
  • Smoking engine
  • Increased emissions
  • Poor throttle response
  • Increased fuel consumption
  • Lack of response under load 

There's also a knock-on effect. A badly performing engine wears out more quickly. All of this has an impact on your transmission, too.

What fuel injector cleaners do 

Fuel injector cleaners are designed to remedy the problems listed above. Your engine will run cleaner and last longer. The effects are most dramatic in older cars that are misfiring or idling badly, but all vehicles can benefit. Your mechanic will probably recommend a fuel injector flush when you get your vehicle serviced. The kind of fuel injector cleaners we're looking at here are a cheaper alternative that you can use yourself.

You add a fuel injector cleaner to your tank along with your gasoline or diesel. It is then pumped through the system during the normal use of your vehicle. There's no need to do anything special other than adding the correct amount to the tank when you fill up. In fact, fuel injector cleaners help clean the whole fuel system.

Fuel injector cleaner ingredients

Exact chemical compositions vary, but basically, these cleaners include a mixture of detergents for cleaning and oils for lubrication. While many of these products are noxious, there is increasing development of environmentally friendly products that use solvent-free detergents and synthetic oils.

Detergent: The two most common detergents are polyether amine (PEA) and polyisobutylene (PIB). These detergents dissolve residues completely (if the residues were just broken down, larger particles from fuel pipes could move through the system and block the injectors). Once dissolved, the residues are injected through into the combustion chamber where they pass harmlessly through the exhaust. (Don't worry. They have no impact on catalytic converters.)

Lubricant: The lubricant also flows through the entire fuel system and into the combustion chambers. The oil applies a thin protective coating to any moving parts it touches, helping cool the system, prevent further buildup and resist corrosion.

Do fuel injector cleaners work?

Are some people disappointed with the results? Yes. A fuel injector cleaner isn’t a miracle performance enhancer. Many manufacturers claim their products will make your car run more smoothly, that performance will be improved and fuel consumption will be reduced. What they're really saying is that those are the benefits you could see when compared with the way your vehicle is running with clogged injectors. Fuel injector cleaner can't make your vehicle run better than new, but the best fuel injector cleaners can make a tremendous difference to an engine that's running badly.

Choosing a fuel injector cleaner for your vehicle

While each manufacturer claims a variety of benefits for its products, almost all fuel injector cleaners do a similar job. These are the points you want to consider before buying:

  • Suitability for your vehicle: Not every product suits every car, truck or motorcycle, so check. Many fuel injector cleaners work with gasoline and diesel, but not all of them do.
  • Frequency of application: For example, do you want to be adding something every time you fill up or just when you change the oil?
  • Cost: The fuel injector cleaners that are used less frequently are often more expensive.
  • Brand: Cheap, no-name products may not live up to the claims. Recognized brands have a reputation to protect and are likely to have spent significantly more on research and development to create a more effective product.
  • User feedback: People are much more likely to complain than compliment. If dozens or hundreds of actual users praise a particular fuel injector cleaner, it must be doing some right.

Tips 

  • Too low a fuel level can affect your fuel pump. The fuel pump is located in the bottom of your tank. If you let the level drop too low, the pump gets hot. It's not enough to cause any danger, but it will reduce its efficiency and working life. Keep your fuel tank a quarter full or above to prevent this.
  • Too low a fuel level can contaminate your fuel tank filter. No fuel is 100% clean, and dirt particles collect in the bottom of the fuel tank. If the tank gets too low, you risk sucking these particles into your fuel tank filter and blocking it.
  • Add fuel injector cleaner to a half-empty tank. Although it's never recommended to let your fuel level get very low, if you're adding a fuel injector cleaner to the tank, you should do it when it's around half empty and then fill with fuel to get the most effective dilution.
  • Know the signs of fuel injector problems. Trouble starting, a rough idle, and difficulty when accelerating or under stress (like when towing) are all symptoms of fuel injector problems. These can also be related to faults in the fuel pump or fuel filter. Using fuel injector cleaner can be a quick, cheap and effective way to resolve one of those problems before you need to look further.

FAQ

Q. How much do fuel injector cleaners cost? 

A. Comparing fuel injector cleaner prices isn’t easy. Containers are different sizes. Dosage amounts and time periods differ.

Cheaper fuel injector cleaners are often intended for regular use. One pack we looked at costing $15 treats 100 gallons of fuel. Another costing $14 should be used every 3,000 miles.

Other cleaners that cost $20 to $25 per bottle, may treat a mere 20 gallons of fuel, but their use-case instructions can be misleading. Many are intended to be used with a single tank of gas but once every 10,000 miles or so. If you have a compact car with a small fuel tank (or a motorcycle) you probably won't need the whole bottle.

Q. How often do I need to use fuel injector cleaner?

A. If you search online for answers to this question, you'll find that everyone has an opinion! Some say every time you fill with gas, some say with every other tank, once a month, once every X thousand miles, and so on. Unless you receive qualified professional advice to the contrary, we recommend following the manufacturer's advice — it knows best what the product can do. Many fuel injector cleaners are intended to treat a given amount of fuel (100 gallons, for example). However, the internal combustion engine is a complex mechanism, and no two are quite the same. If you're dissatisfied with the results you're getting, try a different brand next time.

Q. Can I use fuel injector cleaner in turbocharged or supercharged engines?

A. No problem at all, as long as you're running regular gas or diesel you buy at the pump. As far as we’ve been able to establish, these products haven’t been tested with racing fuels like nitromethane. If you're running any kind of race car, a fuel injector cleaner could have a damaging rather than beneficial effect.

Q. Some people say fuel injection cleaners don't make any difference. Is that true?

A. It’s possible that a particular product didn't make a noticeable difference to an individual vehicle, or that the driver didn't notice a marked improvement. But that doesn't mean the product doesn't work or that you should neglect something that will prolong the life of your vehicle. On a well-maintained, low-mileage engine, the effects will naturally be less dramatic than on an older model with 200,000 miles. Mechanics recommend flushing your injectors from time to time. The overwhelming majority of users we researched reported positive results. It does no harm and can be of tremendous benefit, so what’s the downside?