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10 Best Internal Engine Cleaner of December 2025
List of Top Rated Internal Engine Cleaner from thousands of customer reviews & feedback.
Updated On Dec 2025
1,080 Reviews Studied
1
Liqui Moly 2037 Pro-Line Engine Flush - 500 Milliliters Read Review
- Easy way to clean and flush the oil systems of gasoline and diesel engines
- Gentle and rapid cleaning
- Neutral to seals and other materials installed in the engine
- Compatible with catalytic converters
- Simple to use
2
XADO Special Xtreme Diesel Truck Engine Oil System Flush (Can, 500ml) Read Review
- Thoroughly Cleans The Engine Oil System
- Removes Deposits, Carbon And Sludge
- Restores The Mobility Of Piston Rings
- Due To The Presence Of Revitalizant, Protects The Engine
3
Mercury/Quicksilver Parts 858080K01 POWER TUNE @1 POWER TUNE ENGINE CLEANER Read Review
- SKU: 92-858080K01
- Sold Each
- Please verify your own fitment
4
Throttle Muscle TM5646 - Engine Scrub Super Concentrated Engine Flush Oil System Cleaner Heavy Duty Engine and Crankcase... Read Review
- Helps remove sludge and harmful engine deposits
- Restores engine cleanliness in preparation for new motor oil
- Excellent for use after an extended drain interval or unknown service history
- No extra oil needed during flush (up to six quart capacity)
- Do not rev engine during service - run for no more than 5 minutes
5
XADO Engine Oil System Cleaner with Anti-Carbon Effect - Removes Contamination & Engine Sludge - ATOMEX Total Flush Revi... Read Review
- Safely and carefully cleans engine oil system from all kinds of contaminations, ensures its technical purity
- Removes carbon and restores mobility of stuck piston rings.
- Universal for all engine types including turbo-supercharged ones.
- Due to revitalizant provides creation of engine protection reserve.
- Cleans crankcase ventilation system. Eliminates effect of hydraulic lash adjusters sealing
6
STP High Mileage Engine Flush Formula, Oil cleaning for Cars & Truck, Bottles, 15 Fl Oz, 18566 Read Review
- Scientifically engineered to improve the oil drain for vehicles over 75K Miles
- Super concentrated cleaning agents actively clean deposits in the engine
- Helps Reduce Sludge and Varnish on Cylinder Heads
- Helps dissolve Engine Deposits
- Will not harm seals - safe to use every oil change when used as directed
7
Sea Foam SF-16 Motor Treatment - 16 oz. Read Review
- Cleans injectors, carb jets and passageways
- Cleans and lubricates intake valves, pistons and cylinders
- Dissolves and cleans fuel residue in fuel systems
- Dissolves oil deposits in crankcase
- Clean timing chain tensioners and VVT actuators, quiet noisy lifters
- 100 percent pure petroleum
- EPA registered product
- Liquefies gum and varnish deposits or internal engine contaminants
- Special Shipping Information: This item cannot be returned and has additional shipping restrictions
- Special Shipping Information: This item cannot be returned and has additional shipping restrictions
8
Golden Touch 1698 Fast Flush Engine Flush - 128 fl. oz. Read Review
- Petroleum based formula does not contain kerosene or mineral spirits.
- Made in the USA
- Will not cause leaks, plug ports, galleys or screens; for all domestic and import gasoline engines.
9
Quicksilver 858080Q03 Power Tune Internal Engine Cleaner, 12oz - for 2-Stroke, 4-Stroke and Fuel-Injected Gas Engines Read Review
- Removes harmful deposits that accumulate from normal use
- For use with all 2‐ and 4‐cycle carbureted and fuel‐injected gasoline engines
- Restores power to poor or non-running engines
- 12 ounce spray can
- Improves fuel/air flow and overall engine performance
10
Lubegard 98901 Engine Flush and Protect Pack Read Review
- Safely remove accumulated amounts of varnish, sludge and by-products of combustion
- For use in all diesel and gasoline engines
- Prepares engine for fresh oil
- Protects and extends oil life by 30 percent
- Optimizes engine horsepower and performance
