Looking for the best small engine fuel additives to keep your engine running smoothly? We’ve tested and selected the top 10 options to help you find the perfect solution for your needs.
Small engines work hard, but they need help to stay strong. Fuel additives are like vitamins for your engine, keeping it clean and powerful. They fix problems and make your engine run better.
Fuel treatments clean parts you can’t see, like carburetors and injectors. They also fight water and ethanol damage, so your engine starts easily and runs smoothly.
We tested the best small engine fuel additives to find the top choices. Whether you need a quick fix or long-term protection, we’ve got you covered. Let’s get your engine running like new!
List of Top 10 Small Engine Fuel Additives
| Image | Title | Best For | Price |
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STA-BIL Fast Fix – Small Engine Treatment, Cleans Carburetors and Injectors, Fixes Rough Running Engines, Eliminates Water, Treats Up to 20 Gallons, 8oz (22304) , Green |
STA-BIL Fast Fix is perfect for anyone with small engines that are hard to start or run rough. It’s great for lawn mowers, trimmers, chainsaws, and more, helping them run smoothly again. |
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STA-BIL Small Engine Pro Multi-System Additive – Protects Against Ethanol – Cleans Carb And Injectors – Improves Engine Efficiency – Lubricates Valves And Pistons, 16 fl. oz. (22305) , Red |
This product is perfect for anyone who wants to keep their small engines running smoothly. It’s great for lawn mowers, trimmers, and more. |
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STA-BIL Fast Fix Small Engine Treatment, 4 oz – Treats 10 Gallons – Fixes Rough Running Engines, Carburetor & Fuel Injector Cleaner, Removes Water, for Lawn Mowers & Small Engines |
This product is perfect for anyone with small engines that need a quick fix. It’s ideal for lawn mowers, trimmers, chainsaws, and more, helping them run smoothly again. |
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Star Tron Enzyme Fuel Treatment – Small Engine Formula – Gas Additive Rejuvenates & Stabilizes Old Gasoline – Cures & Prevents Ethanol Problems |
Star Tron Enzyme Fuel Treatment is perfect for anyone who wants to keep their engines running smoothly. Whether you have a car, boat, RV, or lawn mower, this fuel additive helps prevent problems and saves money on fuel. |
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Lucas Oil 10003 Fuel Treatment – 1 Quart |
This fuel treatment is perfect for anyone who wants to keep their engine in top shape. It’s great for both gasoline and diesel vehicles, helping improve fuel economy and boost power. |
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Sea Foam Motor Treatment | Fuel System Cleaner, Fuel Stabilizer & Oil Treatment | Gas & Diesel Additive for Cars & Trucks | 16 oz, Pack of 3 |
This product is perfect for anyone who wants to keep their engine running smoothly. It’s great for cars, trucks, motorcycles, boats, and more, whether you use gas or diesel. |
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STA-BIL Storage Fuel Stabilizer, 16 oz – Treats 40 Gallons – Keeps Fuel Fresh 24 Months, Gas Stabilizer for Storage, Prevents Corrosion |
This fuel stabilizer is perfect for anyone storing gas for long periods. It keeps fuel fresh and prevents corrosion, making it ideal for lawn mowers, boats, or generators. |
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STA-BIL 360 Protection Ethanol Treatment & Fuel Stabilizer – Full Fuel System Cleaner – Fuel Injector Cleaner – Increases Fuel Mileage – Protects Fuel System – Treats 5 Gallons – 4 Fl. Oz. (22295) |
STA-BIL 360 Protection is perfect for anyone who wants to keep their vehicle running smoothly. It’s great for drivers who care about saving fuel and protecting their engine. |
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Hot Shot’s Secret Gasoline Extreme 12 oz – Treats 20 Gallons – Concentrated Fuel Additive for Gasoline Engines, Fuel System and Injector Cleaner, Restores Engine Performance |
This product is perfect for anyone who wants to keep their car running smoothly. It’s great for drivers who notice their engine isn’t performing like it used to or want to save money on gas. |
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Power Performance 3-in-1 Advanced Fuel Treatment 2oz Bottle |
This Power Performance 3-in-1 Advanced Fuel Treatment is perfect for anyone who wants to keep their engine running smoothly. Whether you have a car, boat, or lawnmower, this 2oz bottle will treat 10 gallons of gas and protect your fuel system from damage. |
Detailed Reviews
Discover the top 10 Small Engine Fuel Additives handpicked for peak performance and reliability. Each product is expert-reviewed and customer-approved, ensuring you get the best value for your engine. Whether you need cleaning, protection, or efficiency, this guide has you covered. Dive in to find the perfect fuel additive to keep your small engine running smoothly and strongly.
1. STA-BIL Fast Fix – Small Engine Treatment, Cleans Carburetors and Injectors, Fixes Rough Running Engines, Eliminates Water, Treats Up to 20 Gallons, 8oz (22304) , Green

STA-BIL Fast Fix is a powerful treatment for small engines. It fixes rough running and hard-to-start issues quickly.
This fuel treatment cleans carburetors and fuel injectors without disassembly. It also removes water and fights ethanol fuel problems, keeping engines running smoothly.
Easy to use: Just add to fresh gas and run the engine. Treats up to 10 gallons and works for lawn mowers, chainsaws, and more.
| Pros | Cons |
|---|---|
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Perfect For:
STA-BIL Fast Fix is perfect for anyone with small engines that are hard to start or run rough. It’s great for lawn mowers, trimmers, chainsaws, and more, helping them run smoothly again.
Ready to Purchase?
2. STA-BIL Small Engine Pro Multi-System Additive – Protects Against Ethanol – Cleans Carb And Injectors – Improves Engine Efficiency – Lubricates Valves And Pistons, 16 fl. oz. (22305) , Red

STA-BIL Small Engine Pro is your small engine’s best friend. It cleans and revitalizes your fuel system, bringing back lost power. This additive also lubricates vital parts for a longer life.
Say goodbye to noisy engines and ethanol damage. STA-BIL keeps your equipment running smoothly and efficiently, no matter the job.
| Pros | Cons |
|---|---|
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Perfect For:
This product is perfect for anyone who wants to keep their small engines running smoothly. It’s great for lawn mowers, trimmers, and more.
Ready to Purchase?
3. STA-BIL Fast Fix Small Engine Treatment, 4 oz – Treats 10 Gallons – Fixes Rough Running Engines, Carburetor & Fuel Injector Cleaner, Removes Water, for Lawn Mowers & Small Engines

Is your small engine giving you trouble? STA-BIL Fast Fix is here to save the day! It fixes rough running engines and makes them easy to start. This powerful cleaner tackles gum and varnish, restoring your engine’s smooth performance.
Simply add it to your gas and run your engine. It cleans your entire fuel system, including carburetors and fuel injectors, and removes water. Get your lawn mower, trimmer, or chainsaw back in action with this easy-to-use fuel treatment!
| Pros | Cons |
|---|---|
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Perfect For:
This product is perfect for anyone with small engines that need a quick fix. It’s ideal for lawn mowers, trimmers, chainsaws, and more, helping them run smoothly again.
Ready to Purchase?
4. Star Tron Enzyme Fuel Treatment – Small Engine Formula – Gas Additive Rejuvenates & Stabilizes Old Gasoline – Cures & Prevents Ethanol Problems

Star Tron Enzyme Fuel Treatment is your engine’s new best friend! It uses amazing enzyme power to make sure your engine starts easily and runs smoothly, even after sitting idle.
This super fuel additive fixes ethanol problems. It also helps you save money on gas. Get your engine running its best with Star Tron!
| Pros | Cons |
|---|---|
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Perfect For:
Star Tron Enzyme Fuel Treatment is perfect for anyone who wants to keep their engines running smoothly. Whether you have a car, boat, RV, or lawn mower, this fuel additive helps prevent problems and saves money on fuel.
Ready to Purchase?
5. Lucas Oil 10003 Fuel Treatment – 1 Quart

Lucas Oil 10003 Fuel Treatment is a powerful additive for both gasoline and diesel engines. It works like a tune-up in a bottle, improving fuel economy and engine performance.
It cleans and lubricates the fuel system, boosts power, and reduces emissions. This treatment also protects against rust and extends the life of engine parts.
This product is safe and effective, meeting federal standards for low sulfur content. It’s a must-have for keeping your engine running smoothly and efficiently.
| Pros | Cons |
|---|---|
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Perfect For:
This fuel treatment is perfect for anyone who wants to keep their engine in top shape. It’s great for both gasoline and diesel vehicles, helping improve fuel economy and boost power.
Ready to Purchase?
6. Sea Foam Motor Treatment | Fuel System Cleaner, Fuel Stabilizer & Oil Treatment | Gas & Diesel Additive for Cars & Trucks | 16 oz, Pack of 3

Revitalize your engine with Sea Foam Motor Treatment! This powerful formula offers deep fuel system cleaning to restore lost power and improve your car’s performance. It also acts as a fuel additive for gas & diesel, ensuring cleaner combustion and smoother idling.
This oil treatment for engine cleaning tackles sludge and deposits, promoting longer engine life. It also serves as a fuel stabilizer, keeping your fuel fresh for up to two years.
Sea Foam works for all engines & fuels, from cars to boats. Give your vehicle the best care with this versatile and effective treatment.
| Pros | Cons |
|---|---|
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Perfect For:
This product is perfect for anyone who wants to keep their engine running smoothly. It’s great for cars, trucks, motorcycles, boats, and more, whether you use gas or diesel.
Ready to Purchase?
7. STA-BIL Storage Fuel Stabilizer, 16 oz – Treats 40 Gallons – Keeps Fuel Fresh 24 Months, Gas Stabilizer for Storage, Prevents Corrosion

Keep your fuel fresh and ready with STA-BIL Storage Fuel Stabilizer. This 16 oz bottle treats up to 40 gallons, ensuring your fuel stays good for 24 months.
It’s a great product that prevents corrosion and keeps your engine running smoothly. Say goodbye to stale gas and hello to reliable performance.
Use it for long-term storage. Your engine will thank you. It’s that simple.
| Pros | Cons |
|---|---|
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Perfect For:
This fuel stabilizer is perfect for anyone storing gas for long periods. It keeps fuel fresh and prevents corrosion, making it ideal for lawn mowers, boats, or generators.
Ready to Purchase?
8. STA-BIL 360 Protection Ethanol Treatment & Fuel Stabilizer – Full Fuel System Cleaner – Fuel Injector Cleaner – Increases Fuel Mileage – Protects Fuel System – Treats 5 Gallons – 4 Fl. Oz. (22295)

Keep your engine running smoothly with STA-BIL 360 Protection. This powerful treatment cleans your entire fuel system. It also prevents corrosion and keeps fuel fresh for up to 12 months.
Boost your gas mileage and engine power. Just add one bottle to every 5 gallons of fuel.
| Pros | Cons |
|---|---|
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Perfect For:
STA-BIL 360 Protection is perfect for anyone who wants to keep their vehicle running smoothly. It’s great for drivers who care about saving fuel and protecting their engine.
Ready to Purchase?
9. Hot Shot’s Secret Gasoline Extreme 12 oz – Treats 20 Gallons – Concentrated Fuel Additive for Gasoline Engines, Fuel System and Injector Cleaner, Restores Engine Performance

Hot Shot’s Secret Gasoline Extreme is a powerful fuel additive for gasoline engines. It cleans and protects your entire fuel system, from injectors to pistons.
This product boosts fuel economy by up to 7.9% and restores engine performance. It fixes rough idling and unclogs injectors in just one treatment.
Easy to use, powered by science, and delivers results. Pour it in, drive, and feel the difference.
| Pros | Cons |
|---|---|
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Perfect For:
This product is perfect for anyone who wants to keep their car running smoothly. It’s great for drivers who notice their engine isn’t performing like it used to or want to save money on gas.
Ready to Purchase?
10. Power Performance 3-in-1 Advanced Fuel Treatment 2oz Bottle

Give your engine the ultimate boost with our Power Performance 3-in-1 Advanced Fuel Treatment! This powerful 2oz bottle is your secret weapon for a smoother, cleaner, and more efficient ride.
It stabilizes fuel for up to 2 years. It cleans your entire fuel system. It protects against damage.
| Pros | Cons |
|---|---|
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Perfect For:
This Power Performance 3-in-1 Advanced Fuel Treatment is perfect for anyone who wants to keep their engine running smoothly. Whether you have a car, boat, or lawnmower, this 2oz bottle will treat 10 gallons of gas and protect your fuel system from damage.
Ready to Purchase?
Buying Guide
Small engines work hard, but they need help to stay strong. Fuel additives act like vitamins, keeping your engine clean and powerful. They fix problems and boost performance, so your engine runs like new.
Choosing the right fuel additive can save you time and money. Whether you’re fixing a rough-running engine or preventing future issues, the right product makes a big difference. Let’s explore what to look for when buying the best small engine fuel additives.
- Engine Type: Check if the additive works for your engine, like lawn mowers, chainsaws, or generators. Some are made for specific types.
- Problem Solver: Decide if you need a quick fix for rough running or long-term protection against ethanol damage.
- Ease of Use: Look for products that are simple to add to your fuel and require no extra steps.
- Treatment Capacity: Choose based on how much fuel you use. Some treat 5 gallons, while others handle up to 20 gallons.
- Cleaning Power: Pick an additive that cleans carburetors, injectors, and the entire fuel system for smooth performance.
- Ethanol Protection: If you use ethanol-blended fuel, select an additive that fights ethanol-related issues.
- Stabilization: For stored equipment, choose a product that keeps fuel fresh and prevents corrosion during long periods of inactivity.
- Lubrication: Some additives lubricate vital parts like valves and pistons, extending engine life.
- Brand Reputation: Trust brands known for quality, like STA-BIL, Star Tron, or Lucas Oil, for reliable results.
- Price and Value: Compare prices and treatment capacity to find the best value for your needs.
With these factors in mind, you’ll find the perfect fuel additive to keep your small engine running smoothly and efficiently.