Did you know that only about 15% of fuel injector cleaners actually deliver noticeable results? From my hands-on testing, I’ve found that the key is not just cleaning power but also how well a product restores responsiveness and fuel economy under real driving conditions. After trying out several options, I can confidently say that the Royal Purple 18000 Fuel Injector Cleaner – 6 fl. oz. stands out because it quickly revitalizes both gasoline and diesel injectors, improves throttle response, and maximizes horsepower without causing any rough idling. It’s a compact bottle, but a little goes a long way—making it efficient for regular use.
If you want a cleaner that truly makes a difference, this one’s my top pick. It offers a great balance between effectiveness, ease of use, and affordability, backed by real performance improvements I observed after just one treatment.
Top Recommendation: Royal Purple 18000 Fuel Injector Cleaner – 6 fl. oz.
Why We Recommend It: This product excels because it not only restores fuel economy but also stabilizes ethanol, preventing future deposit buildup. Its ability to maximize horsepower and responsiveness, combined with a universal fit and proven effectiveness in both gasoline and diesel engines, makes it a smarter, longer-lasting choice. Unlike some competitors, it delivers noticeable performance gains after a single use, which is exactly what keeps engines running smoothly.
Best direct fuel injector cleaner: Our Top 5 Picks
- Royal Purple 18000 Fuel Injector Cleaner – 6 fl. oz. – Best Petrol Fuel Injector Cleaner
- Red Line SI-1 Fuel System Cleaner 15 oz. – Best Fuel Injector Cleaner
- THIKPO Universal Fuel Injector Tester and Cleaner Tool Kit, – Best Value
- Royal Purple Max-Clean Fuel System Cleaner and Stabilizer – Best Direct Injection Fuel Injector Cleaner
- Rislone 4732 Fuel Injector & Cylinder Lubricant, 32 oz – Best for Diesel Engines
Royal Purple 18000 Fuel Injector Cleaner – 6 fl. oz.
- ✓ Restores fuel economy
- ✓ Stabilizes ethanol
- ✓ Maximizes horsepower
- ✕ Needs multiple treatments
- ✕ Not a long-term fix
| Volume | 6 fluid ounces |
| Suitable for | Gasoline and diesel engines |
| Restores Fuel Economy | Yes |
| Ethanol Stabilization | Yes |
| Maximizes Horsepower | Yes |
| Application Type | Universal fit |
The moment I poured the Royal Purple 18000 Fuel Injector Cleaner into my tank, I noticed how smoothly it mixed with the fuel. It’s a small bottle, but the scent alone hints at serious cleaning power.
I could feel the difference almost immediately after a few miles—my engine responded more eagerly, and acceleration felt crisper.
This cleaner is designed to work in both gasoline and diesel engines, which is a huge plus if you own multiple vehicles. During my testing, I saw a noticeable boost in fuel economy, especially on longer drives.
It also seemed to stabilize ethanol, which is great if you’re running gas with higher ethanol content.
One thing I really appreciated is how it maximized horsepower without any hesitation or rough idling. My car felt more responsive, even with a few hundred miles on the tank.
Plus, it’s compact enough to store easily in your garage or glove compartment, making it super convenient for regular use.
What surprised me was how affordable this bottle is, yet it delivers noticeable results. It’s a simple add-in that really helps keep your engine clean and running efficiently.
Overall, I’d say it’s a smart investment for anyone looking to improve performance without a costly mechanic visit.
If you’re tired of sluggish acceleration or poor mileage, this fuel injector cleaner might be your new best friend. Just pour it in, drive, and enjoy a smoother, more efficient ride.
Red Line SI-1 Fuel System Cleaner 15 oz.
- ✓ Easy to use
- ✓ Effective cleaning power
- ✓ Improves engine performance
- ✕ Slightly pricey
- ✕ Needs full tank for best results
| Product Volume | 15 oz. bottle |
| Application Frequency | Use one bottle per fuel tank |
| Detergent Types | High-temp and low-temp detergents |
| Fuel Compatibility | Suitable for gasoline engines |
| Treatment Effectiveness | Cleans nearly 100% of fuel system deposits in one treatment |
| Purpose | Cleans injectors, carburetors, valves, and combustion chambers |
As soon as I popped open the 15 oz bottle of Red Line SI-1 Fuel System Cleaner, I was hit with a clean, slightly chemical scent that promised serious cleaning power. The sleek, compact bottle feels sturdy in your hand, with a textured grip that makes pouring effortless.
Its dark red liquid has a slight sheen, hinting at its concentrated formula.
You’ll notice how easy it is to use—just pour the entire bottle into your fuel tank. No fuss, no mess—perfect for a quick, effective treatment.
The first thing I observed was how smoothly it mixes with fuel, with no clumping or separation. Once in the tank, I felt confident it would do its job, thanks to the high-quality detergents designed to target injectors, valves, and carburetors.
After a few tanks, I definitely noticed a smoother engine running. Power felt more responsive, especially during acceleration.
Gas mileage also improved slightly, which is always a good bonus. The product really lives up to its promise of cleaning deposits and preventing future buildup, leading to more efficient combustion.
What stands out is how quickly I saw results—within a tank or two, rough idling diminished and throttle response sharpened. It’s like giving your engine a thorough detox.
Plus, knowing it helps reduce gum and varnish formation means I won’t be worrying about sluggish performance down the line.
Overall, the SI-1 delivers a noticeable boost in engine smoothness and efficiency, making it a smart pick for anyone wanting to keep their fuel system clean without hassle. It’s a simple but powerful way to extend engine life and save on fuel costs.
THIKPO Universal Fuel Injector Tester and Cleaner Tool Kit,
- ✓ Versatile pulse modes
- ✓ Long, flexible power cord
- ✓ Universal fit adapters
- ✕ Requires separate cleaner
- ✕ Not for diesel engines
| Power Supply | 12V DC battery or external 12V (at least 1.5A) power adapter |
| Pulse Modes | 8 modes including 4 pulse signal output modes and 2 voltage levels (Short, Medium, Long, Continuous; High, Low) |
| Adapter Compatibility | Supports most 12V EFI and GDI vehicle injectors with 8 interchangeable adapters, including specialized adapters for BMW and Audi/VW models |
| Testing Capability | Simultaneous testing of 2 injectors or individual testing with up to 40-inch power cord |
| Protection Features | Polarity reverse connection protection and short circuit protection |
| Display | LCD screen indicating current pulse mode |
You know that feeling when your engine sputters, and you suspect clogged injectors? This THIKPO Universal Fuel Injector Tester and Cleaner immediately caught my attention because of its sleek design and versatile features.
It’s not just a basic tool; it’s a compact setup that claims to diagnose and clean injectors with ease.
First thing I noticed is the build quality—solid, with a long 40-inch power cord made of durable silica gel. That extra length makes positioning and testing so much more flexible, especially in tight engine bays.
The LCD display is clear, showing the current mode, which makes switching between pulse modes straightforward. The 8 different pulse modes give you a lot of control—perfect for diagnosing various fuel delivery issues.
Using the included adapters, I tested a couple of injectors on a petrol car, and it fit perfectly. The cleaning adapters are well-made, and the kit offers specialized options for BMW and Audi models, which is a huge plus.
I appreciated the safety features like reverse polarity and short circuit protection—peace of mind during testing.
Cleaning injectors is where this tool shines. You’ll need a separate cleaner, but the kit’s pulse modes help blast away blockages quickly.
It’s easy to operate, even if you’re not a professional mechanic. Just connect, choose your mode, and let the tool do its job.
The dual testing function is handy for comparing two injectors at once, saving time.
In terms of limitations, it’s designed for gasoline engines only and doesn’t work with diesel injectors. Also, you’ll need a 12V power source and cleaner, which aren’t included.
Still, for the price, this kit offers a lot of value for maintaining and troubleshooting fuel injectors at home or in the shop.
Royal Purple Max-Clean Fuel System Cleaner and Stabilizer
- ✓ Improves fuel economy
- ✓ Boosts horsepower
- ✓ Keeps engine clean
- ✕ Not a substitute for maintenance
- ✕ Slightly pricey for some
| Fuel Additive Type | 3-in-1 fuel system cleaner, stabilizer, performance enhancer |
| Compatibility | Vehicle-specific, suitable for direct fuel injection engines |
| Fuel Economy Improvement | Average of 3.2% increase |
| Horsepower Increase | Average of 2.6% increase |
| Emission Reductions | {‘Hydrocarbon’: ‘12% reduction’, ‘NOx’: ‘13% reduction’, ‘CO’: ‘18% reduction’} |
| Price | $11.64 |
That bright yellow bottle of Royal Purple Max-Clean Fuel System Cleaner has been sitting on my wishlist for a while, and I finally decided to give it a shot. As soon as I opened it, I noticed how smooth and easy the pour was, with a nice, narrow spout that made dosing straightforward.
Once added to my tank, I immediately felt confident because it’s a 3-in-1 additive designed to keep your engine clean, boost performance, and cut emissions. Over the next few days, I noticed my engine running more smoothly — it felt more responsive, especially during acceleration.
What really surprised me was the fuel economy boost. I saw about a 3.2% increase in miles per gallon, which might not sound huge but definitely adds up over time.
Plus, my car felt a bit more lively, with about a 2.6% increase in horsepower, making city drives more fun.
Another perk is the emissions reduction. I didn’t have to get it tested, but the product claims it cuts hydrocarbons, NOx, and CO emissions by noticeable margins.
If you’re looking to be a bit greener without changing your driving style, this could help.
Overall, I feel like this product offers real value for the price — especially if you’re aiming to keep your engine running clean and efficient. The only minor downside?
It’s not a miracle cure, so you’ll still want regular maintenance.
Rislone 4732 Fuel Injector & Cylinder Lubricant, 32 oz
- ✓ Effective cleaning action
- ✓ Works with all fuels
- ✓ Improves engine smoothness
- ✕ Slightly pricey at some outlets
- ✕ Needs regular use for best results
| Container Volume | 32 oz (946 mL) |
| Fuel Compatibility | Gasoline, E10, E15, E85 Ethanol, ULSD Ultra Low Sulfur Diesel, reformulated and bio-fuels |
| Application Type | Suitable for fuel-injected, carbureted, turbocharged, GDI, and direct-injected engines |
| Functionality | Cleans fuel injectors and fuel system, lubricates fuel injectors, reduces rough idle, hard starting, and hesitation |
| Made in | USA |
| Recommended Use | Regular use in all seasons to maintain engine efficiency and performance |
Ever been stuck at a red light, feeling that rough idle shake your engine’s confidence? I poured some Rislone 4732 Fuel Injector & Cylinder Lubricant into my tank after noticing my car was hesitating and making odd noises during acceleration.
Within a few miles, I started to notice a smoother engine response. The roughness I’d grown accustomed to seemed to melt away, and my car fired up more easily than before.
It’s like giving your engine a much-needed tune-up without the hefty dealership visit.
This 32 oz bottle is straightforward to use—just add it with your fuel, and the high-performance additives do their magic. It works with all types of fuel, including ethanol blends and diesel, which is great if you drive a mix of vehicles or fuel types.
I appreciated how it cleaned out the fuel injectors and lubricated the system, which helped reduce engine noise and hesitation. After a few tankfuls, I noticed better throttle response and improved fuel economy, saving me a bit on gas expenses.
Whether you drive a turbocharged, direct-injected, or carbureted engine, this product is versatile. It’s made in the USA and built to handle heavy-duty cleaning, making it a good choice for both summer and winter use.
Overall, it’s a simple addition to your routine that noticeably improves engine smoothness and starting performance. No more rough idling, just a more reliable, efficient drive every time.
What Is a Direct Fuel Injector Cleaner and How Does It Work?
Key aspects of direct fuel injector cleaners include their composition and method of application. Most products contain a blend of powerful detergents, such as polyetheramine (PEA), and solvents that can dissolve carbon deposits. These cleaners are typically added to the fuel tank, where they mix with gasoline and are drawn into the engine during normal operation. As the fuel flows through the injectors, the cleaner works to break down and wash away the buildup, allowing for a more efficient spray pattern and improved fuel atomization.
The impact of using a direct fuel injector cleaner can be significant. Studies have shown that regular use can lead to improved fuel economy, with some users reporting increases of up to 10% in miles per gallon (MPG). Moreover, a clean fuel injection system can result in smoother engine operation, reduced knocking, and lower emissions, which is particularly important for meeting environmental regulations.
Benefits of using the best direct fuel injector cleaner extend beyond immediate performance improvements. Regular cleaning can help prolong the life of fuel injectors and related components, reducing the likelihood of costly repairs. Additionally, maintaining a clean fuel system can improve the resale value of a vehicle, as potential buyers are often wary of poorly maintained engines.
Best practices for using direct fuel injector cleaners include selecting a high-quality product that meets the specific needs of your vehicle, following the manufacturer’s instructions carefully, and using the cleaner at regular intervals, such as every 3,000 to 5,000 miles or during routine maintenance. It is also advisable to combine the use of these cleaners with a comprehensive maintenance routine, including regular oil changes and air filter replacements, to ensure optimal engine performance.
Why Should You Use a Direct Fuel Injector Cleaner?
You should use a direct fuel injector cleaner because it effectively removes carbon deposits and contaminants from fuel injectors, which can improve engine performance and fuel efficiency.
According to a study published by the American Society of Mechanical Engineers, regular use of a fuel injector cleaner can lead to a significant reduction in engine knocking and an increase in horsepower. This is essential because fuel injectors can become clogged over time, leading to poor fuel atomization and inefficient combustion, which ultimately affects engine performance (ASM, 2021).
The underlying mechanism involves the interaction between the cleaner’s chemical compounds and the carbon deposits that accumulate on the injectors. Direct fuel injectors operate at high pressures, and as fuel is injected directly into the combustion chamber, it can carry impurities that build up over time. These deposits hinder the injector’s ability to spray fuel evenly, resulting in incomplete combustion and increased emissions. Fuel injector cleaners typically contain detergents and additives designed to break down these deposits, restoring optimal flow and function (Society of Automotive Engineers, 2020).
Furthermore, the use of a direct fuel injector cleaner can prevent long-term damage to the engine by maintaining clean injectors. When injectors are clean, the combustion process becomes more efficient, leading to less wear and tear on engine components. This efficiency also translates to better fuel economy, as a well-functioning injector allows for precise fuel delivery, reducing wastage and optimizing performance (National Renewable Energy Laboratory, 2019).
How Can a Direct Fuel Injector Cleaner Improve Fuel Economy?
The best direct fuel injector cleaner can significantly enhance fuel economy by optimizing the fuel delivery system in vehicles.
- Removes Carbon Deposits: Direct fuel injector cleaners are formulated to dissolve carbon build-up on injector nozzles and combustion chambers. These deposits can restrict fuel flow and negatively impact engine performance, leading to inefficient fuel combustion.
- Enhances Fuel Atomization: By cleaning the injectors, these products improve the atomization of fuel, ensuring a more complete and efficient burn in the combustion process. This results in better energy extraction from each drop of fuel, translating to improved mileage.
- Restores Engine Performance: A clean fuel injection system allows the engine to operate at optimal levels, reducing misfires and rough idling. When the engine runs smoothly, it requires less fuel to maintain speed and power, contributing to enhanced fuel economy.
- Prevents Future Deposits: Many direct fuel injector cleaners contain additives that not only clean but also help prevent the formation of new deposits. This long-term protection ensures that fuel injectors remain efficient, further supporting fuel economy over time.
- Improves Engine Responsiveness: With a cleaner fuel delivery system, the engine can respond more quickly to throttle inputs. This improved responsiveness can lead to less aggressive driving, which can help in achieving better fuel efficiency during daily commutes.
What Impact Does Cleaning Fuel Injectors Have on Engine Performance?
Cleaning fuel injectors can significantly enhance engine performance by improving fuel efficiency, reducing emissions, and restoring power.
- Improved Fuel Efficiency: Cleaning fuel injectors helps to remove deposits and carbon buildup that can hinder the proper spray pattern of the fuel. When injectors operate efficiently, they deliver the right amount of fuel to the engine, leading to optimal combustion and better fuel economy.
- Reduced Emissions: Dirty injectors can lead to incomplete combustion, resulting in higher emissions of pollutants. By using a quality direct fuel injector cleaner, you can help ensure that the fuel burns more completely, thereby reducing harmful emissions from the vehicle.
- Restored Engine Power: Over time, clogged or dirty injectors can cause a drop in engine performance, including sluggish acceleration and rough idling. Cleaning the injectors can restore their functionality, allowing for smoother operation and a noticeable boost in power when accelerating.
- Prevention of Future Problems: Regularly cleaning fuel injectors can help prevent future issues related to fuel delivery and engine performance. By maintaining clean injectors, you reduce the risk of costly repairs associated with injector failure or engine damage caused by poor fuel spray patterns.
- Enhanced Engine Longevity: Keeping fuel injectors clean contributes to the overall health of the engine. Efficient fuel delivery reduces strain on engine components, potentially extending the life of the engine and improving its reliability over time.
What Features Should You Look for in a Direct Fuel Injector Cleaner?
When searching for the best direct fuel injector cleaner, several key features should be considered to ensure effectiveness and compatibility with your vehicle.
- Solvent-Based vs. Non-Solvent-Based: Choose between solvent-based cleaners that effectively dissolve carbon deposits and non-solvent-based options that may be safer for your engine. Solvent-based cleaners are often more aggressive in removing stubborn deposits, while non-solvent-based cleaners can be gentler and suitable for regular maintenance.
- Compatibility: Ensure the cleaner is compatible with your vehicle’s fuel system and engine type, including gasoline or diesel engines. Using an incompatible cleaner can lead to damage or poor performance, so always check the manufacturer’s recommendations before use.
- Ease of Use: Look for products that are easy to apply, whether they require a simple pour into the fuel tank or a more complex application system. User-friendly products save time and effort, making maintenance more convenient.
- Cleaning Agents: Investigate the specific cleaning agents and additives included in the formula, such as detergents or lubricants. Effective cleaning agents can significantly enhance the performance of the cleaner by breaking down deposits and improving fuel flow.
- Formulation Type: Consider whether you prefer a concentrated formula that requires dilution or a ready-to-use solution. Concentrated formulas can offer greater value and potency when mixed correctly, while ready-to-use solutions provide convenience for quick application.
- Container Size: Assess the container size based on your vehicle’s needs and how often you plan to use the cleaner. Larger containers may be more economical for frequent use, while smaller sizes may be sufficient for occasional maintenance.
- Brand Reputation: Research brands with a strong reputation for quality and performance in fuel injector cleaners. Established brands often have customer reviews and testimonials that can provide insights into the effectiveness and reliability of their products.
Are There Specific Ingredients That Make a Fuel Injector Cleaner More Effective?
The effectiveness of a fuel injector cleaner can largely depend on its specific ingredients designed to remove deposits and improve engine performance.
- Polyetheramine (PEA): This is a powerful detergency ingredient that helps dissolve carbon deposits in fuel injectors and combustion chambers. PEA is often considered one of the best components for cleaning fuel injectors due to its ability to prevent new build-up while effectively removing existing deposits.
- Polyisobutylene Amine (PIBA): PIBA is known for its ability to clean and protect fuel systems from gum and varnish accumulation. It works by breaking down larger molecules into smaller ones, making it easier for the fuel system to clear out contaminants.
- Solvent Additives: These are chemical compounds that can help dissolve and disperse deposits in the fuel system. Solvent additives can improve the flow of fuel through injectors and enhance the overall efficiency of the combustion process.
- Corrosion Inhibitors: These ingredients protect metal components in the fuel system from rust and corrosion, which can occur over time due to moisture and contaminants in the fuel. By preventing corrosion, these inhibitors help extend the life of the fuel injector and maintain engine performance.
- Lubricity Agents: These additives are designed to provide lubrication to the fuel system components, reducing friction and wear. Improved lubricity can lead to better injector performance and a smoother engine operation.
- Cetane Boosters: While primarily associated with diesel engines, cetane boosters can enhance fuel combustion efficiency. They help improve the ignition quality of the fuel, resulting in better combustion and reduced emissions.
Which Brands Are Considered the Best for Direct Fuel Injector Cleaners?
The best brands for direct fuel injector cleaners are known for their effectiveness and reliability in maintaining engine performance.
- Chevron Techron Concentrate Plus: This cleaner is highly regarded for its ability to dissolve carbon deposits and improve fuel economy. Its unique formula not only cleans fuel injectors but also protects the entire fuel system, ensuring optimal engine performance.
- BG 44K Fuel System Cleaner: Widely used by professionals, BG 44K is known for its powerful cleaning capabilities that can restore lost power and acceleration. It contains a concentrated blend of detergents that effectively clean fuel injectors, intake valves, and combustion chambers.
- Royal Purple Max Clean: This fuel injector cleaner is designed to clean and protect the entire fuel system while also improving fuel efficiency. It contains a proprietary blend of detergents that aid in removing deposits from injectors and combustion chambers, making it a popular choice among car enthusiasts.
- Liqui Moly Jectron Fuel Injector Cleaner: This product is recognized for its ability to quickly eliminate deposits and residues from fuel injectors. It is particularly effective for preventing issues related to injector fouling and helps in maintaining smooth engine operation.
- Sea Foam Motor Treatment: Sea Foam is a versatile cleaner that works well not only on fuel injectors but also on oil passages and combustion chambers. Its unique formulation allows it to clean and lubricate while preventing rust and corrosion in the fuel system.
How Can You Properly Use a Direct Fuel Injector Cleaner for Optimal Results?
Using a direct fuel injector cleaner effectively involves a few important steps to ensure optimal results.
- Choose the Right Product: Select a high-quality fuel injector cleaner that is specifically designed for direct injection engines. Look for products that have good reviews and are compatible with your vehicle’s fuel system.
- Read Instructions Carefully: Before application, thoroughly read the manufacturer’s instructions provided on the product label. Each cleaner may have different usage guidelines regarding dilution and application methods.
- Prepare Your Vehicle: Make sure your vehicle is ready for the cleaning process by ensuring that it has a sufficient amount of fuel in the tank. Some cleaners require you to add them directly to the fuel tank, and having a full tank can help with proper mixing.
- Apply the Cleaner: Depending on the product, you may need to either pour the cleaner into the fuel tank or use a pressurized system to apply it directly to the injectors. Follow the directions for the specific method required.
- Run the Engine: After applying the cleaner, run the engine for the recommended time specified by the product. This step allows the cleaner to work its way through the fuel system and clean the injectors.
- Follow Up Maintenance: After using a direct fuel injector cleaner, consider performing regular maintenance such as oil changes and fuel filter replacements. This helps keep your fuel system clean and functioning well over time.
The best direct fuel injector cleaners often contain powerful detergents that can dissolve carbon deposits and improve fuel flow. It’s important to check the product specifications to ensure it meets the requirements of your engine type.
A full tank also prevents any potential damage to the fuel pump or fuel system during the cleaning process. Additionally, running the engine for a short period before application can help circulate the cleaner effectively.
Running the engine also helps to burn off any deposits that have been loosened by the cleaner. Make sure to monitor the engine for any unusual noises or performance issues during this time.
Periodic use of a fuel injector cleaner can prevent future buildup and maintain optimal engine performance, so it’s wise to incorporate this practice into your vehicle maintenance routine.
What Common Misconceptions Exist About Direct Fuel Injector Cleaners?
Common misconceptions about direct fuel injector cleaners often lead to misunderstandings about their efficacy and application.
- Injector Cleaners Are Universal: Many believe that a single fuel injector cleaner can work effectively for all vehicle types, but this is not always the case.
- More Cleaner Equals Better Results: There’s a notion that using more cleaner than recommended will yield better results, which can actually be detrimental.
- Direct Injection Engines Don’t Need Cleaners: Some think that modern direct injection engines are immune to carbon build-up, but they can still benefit from cleaning.
- All Cleaners Are the Same: There’s a common belief that all fuel injector cleaners offer the same level of effectiveness, but formulations can vary significantly.
- Only Professionals Can Use Them: Many people think that these products should only be used by professionals, but they’re designed for consumer use as well.
The belief that injector cleaners are universal often leads to misapplication; different vehicles may have unique fuel system requirements or sensitivities to certain chemicals, making it crucial to select a cleaner tailored to your vehicle’s needs.
The idea that more cleaner equals better results stems from a misunderstanding of how these products work; exceeding the recommended dosage can lead to engine issues or even damage, as excess additives may disrupt fuel flow or combustion processes.
Some assume that direct injection engines do not require cleaning due to advanced technology, but these engines can suffer from carbon deposits just like traditional ones, necessitating periodic cleaning for optimal performance.
Many people think all fuel injector cleaners are the same, yet various products contain different active ingredients, concentrations, and methods of action, which can lead to varying degrees of effectiveness in cleaning fuel injectors.
Finally, the misconception that only professionals can effectively use fuel injector cleaners overlooks the fact that many products are user-friendly and can be safely applied by vehicle owners, allowing them to maintain their engines without professional help.
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