Best Fuel Additives (2026 Guide)
We selected products by aggregated user rating and review volume, emphasizing formulations for storage stabilization, injector cleaning, and engine/fuel maintenance
Top Picks
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1
STA-BIL Storage Fuel Stabilizer 4 oz (8 Pack)
Keeps gasoline fresh for storage up to 24 months and protects against corrosion. Helps fuel systems perform during long storage and startup, with praise for long-term gas stability
- preserves fuel up to 24 months
- protects against ethanol and non-ethanol fuel corrosion
- enhances fuel system longevity
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2
STA-BIL Storage Fuel Stabilizer 1 Gallon
Keeps gasoline fresh for up to 24 months and protects fuel systems from corrosion. Useful for winter storage and emergency generators, with positive feedback on long-term storage and start-up reliability
- 24-month fuel freshness
- gasoline protection from corrosion
- ethanol and non-ethanol compatibility
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3
Engine & Fuel Formula Kit by zMAX
ZMAX Engine & Fuel Formula Kit uses micro-lubrication to reduce carbon build-up and lubricate metal surfaces, improving efficiency. Customers report smoother idle and better fuel economy with older engines
- micro-lubrication for metal surfaces
- reduces carbon deposit build-up
- improves fuel efficiency and performance
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4
STA-BIL Marine Fuel System Cleaner & Injector Cleaner 1 gal
Marine fuel system cleaner that removes water, gum and varnish while cleaning injectors, lines, and pumps. Provides fuel system protection and smoother starts in marine engines. Customer note: effective for marine applications and helps engines start reliably in spring
- Cleans entire fuel system
- Removes water and deposits
- Marine-oriented protection
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5
STA-BIL Marine Fuel System Cleaner & Injector Cleaner 8oz (12 Pack)
Marine fuel system cleaner with PEA additives cleans fuel injectors, lines, and pumps while removing water, gum, and varnish. Helps keep fuel fresh and improves start-up in spring, according to customers
- Fuel system cleaner with PEA
- Cleans injectors, lines, and pumps
- Removes water and varnish
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6
STA-BIL Marine Fuel System Cleaner & Injector Cleaner 10oz (12 Pack)
Fuel system cleaner for boats that removes water, gum, and varnish using PEA additives to clean injectors, lines, and pumps. Customers report improved reliability and fuel stability in marine use
- full fuel system cleaner
- removes water and varnish
- marine application
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7
STA-BIL In-Season Protection Fuel System Treatment
Fuel system cleaner that cleans injectors, lines, and pumps while preventing water and gum buildup. Improves fuel delivery and helps fuel stay fresh; customers note good performance with ethanol-added gas and smoother idle
- Cleans entire fuel system
- Prevents corrosion and water buildup
- Improves fuel stability and delivery
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8
Ethanol Shield Fuel Stabilizer 24 oz (2 Pack) – keeps fuel fresh
A fuel stabilizer that slows fuel aging and helps moisture removal. Noted to keep small engines cranking and stabilize gasoline over time
- reduces fuel aging
- moisture removal
- phase separation inhibitor
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9
2-Cycle Pre-Blended Fuel for Outdoor Power Equipment (32 oz. x6)
Pre-blended fuel for 2-cycle, air-cooled engines requiring a 50:1 mix. Delivers convenient, ready-to-use fuel with stable quality. Customers note easy pouring and reliable starting on first pull
- pre-blended 50:1 mix
- suitable for portable gas-powered equipment
- ease of pouring and use
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10
TruFuel 4-Cycle Ethanol-Free Fuel (32 oz, case of 6)
Premixed, ethanol-free fuel for 4-cycle outdoor power equipment in portable 32 oz containers. Reduces ethanol-related moisture issues and stabilizes carburetors. Customers report easy starts and ease of pouring
- ethanol-free formula
- premixed for 4-cycle engines
- compact 32 oz container