Exhaust System Cleaner: 5 Top Picks Compared

If your car feels sluggish, fails emissions, or triggers a check engine light, an exhaust system cleaner might be the simple fix you need. These additives target carbon buildup in catalytic converters, oxygen sensors, and fuel injectors to restore efficiency.

This guide compares five top-rated cleaners, from gasoline and diesel formulas to value packs. You’ll discover which product best suits your vehicle and driving habits, helping you save on repairs and improve performance.

Cataclean 16oz – Pass Emissions with Confidence

Cataclean’s 16-ounce formula is specifically designed to reduce carbon buildup in catalytic converters, oxygen sensors, fuel injectors, and cylinder heads. By cleaning these critical components, it helps restore engine power, improve fuel economy, and clear common check engine light codes like P0420 and P0430. This makes it a go-to choice if you’re facing an emissions test soon.

Using it is straightforward: pour the entire bottle into a low fuel tank (around a quarter full), then drive for at least 15 minutes. The cleaner works through the entire fuel and exhaust system, targeting deposits that hinder performance. Many users report a noticeable improvement in drivability and a passed emissions test shortly after treatment.

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• PASS EMISSIONS TESTS WITH CONFIDENCE: Cataclean is specifically formulated to reduce carbon build-up and clean vital components like catalytic converters, injectors and oxygen sensors, helping your vehicle meet stringent smog and emissions standards. Reduces hydrocarbon emissions on gas motors by up to 50%!
• ENHANCE FUEL ECONOMY AND PERFORMANCE: Cataclean cleans fuel injectors and cylinder heads, leading to improved fuel combustion, better mileage, and restored engine power.
• CLEAR CHECK ENGINE LIGHTS: By cleaning your car’s exhaust and fuel systems, Cataclean restores optimal performance and helps resolve common check engine light codes like P0420, P0430, P0171, P0174, P0300, and P0401, potentially saving you thousands on repairs.
• MAINTAIN CATALYTIC CONVERTER EFFICIENCY: Regular use of Cataclean helps prevent carbon accumulation in your catalytic converter, ensuring it operates efficiently and prolongs its lifespan.
• EASY APPLICATION: Simply add Cataclean to your fuel tank as directed; no special tools or mechanical skills required, making it a convenient addition to your vehicle maintenance routine. Safe for use in gasoline, diesel and hybrid engines. 50-state legal.

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Cataclean 1200 Series – Trusted Gasoline Formula

This Cataclean variant, the 1200 series, shares the same 16-ounce formulation as its counterpart but is often packaged for specific retail channels. It targets carbon deposits in catalytic converters, oxygen sensors, fuel injectors, and cylinder heads, aiming to restore performance and fuel economy. If you’re dealing with a rough idle, hesitation, or lost power, this cleaner can help.

Like the standard Cataclean, you add it to a near-empty tank and drive for at least 15 minutes. It’s safe for gasoline, hybrid, and flex-fuel vehicles, and it won’t harm oxygen sensors or catalytic converters. Regular use every 3,000 miles can help maintain system cleanliness and prevent check engine lights from returning.

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• PASS EMISSIONS TESTS WITH CONFIDENCE: Cataclean is specifically formulated to reduce carbon build-up and clean vital components like catalytic converters, injectors and oxygen sensors, helping your vehicle meet stringent smog and emissions standards. Reduces hydrocarbon emissions on gas motors by up to 50%!
• ENHANCE FUEL ECONOMY AND PERFORMANCE: Cataclean cleans fuel injectors and cylinder heads, leading to improved fuel combustion, better mileage, and restored engine power.
• CLEAR CHECK ENGINE LIGHTS: By cleaning your car’s exhaust and fuel systems, Cataclean restores optimal performance and helps resolve common check engine light codes like P0420, P0430, P0171, P0174, P0300, and P0401, potentially saving you thousands on repairs.
• MAINTAIN CATALYTIC CONVERTER EFFICIENCY: Regular use of Cataclean helps prevent carbon accumulation in your catalytic converter, ensuring it operates efficiently and prolongs its lifespan.
• EASY APPLICATION: Simply add Cataclean to your fuel tank as directed; no special tools or mechanical skills required, making it a convenient addition to your vehicle maintenance routine. Safe for use in gasoline, diesel and hybrid engines. 50-state legal.

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Rislone 4720 Cat Complete – All-in-One System Cleaner

Rislone’s 4720 Cat Complete is a 16.9-ounce cleaner that works on the entire fuel, exhaust, and emissions system. It’s designed to increase power, performance, and mileage while saving gas. The formula is safe for gasoline, ethanol, and hybrid engines, and it won’t void your manufacturer’s warranty. Regular use every 5,000 miles can help prevent check engine lights and expensive repairs.

This cleaner is compatible with fuel-injected, direct-injected, carbureted, turbo, GTDI, Ecotec, and EcoBoost engines. It exceeds EPA compliance standards, so you can use it with confidence. Simply add it to your fuel tank and drive normally; the cleaner works as you go, targeting deposits in the catalytic converter, oxygen sensors, and fuel system.

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• Increase power, performance, mileage and save gas: Cleans by not only the entire emissions and exhaust system, but the fuel system as well. Works with gasoline, ethanol and hybrid vehicles.
• Save on expensive fuel system and emission control repairs: Regular use every 5,000 miles tunes-up the fuel, emissions and exhaust systems keeping them clean and preventing the CEL light from returning.
• Will not void manufacturer’s new vehicle warranty: Specifically designed and safe to use on vehicles which have oxygen sensors and catalytic converters. Exceeds EPA compliance performance criteria.
• Works on all fuel injected, direct injected, carbureted, turbo, GTDI, Ecotec and EcoBoost engines.
• DON'T GAMBLE ON AN UNPROVEN BRAND: A leaking engine, head gasket, cooling system, power steering or transmission is your one shot to avoid a bigger repair bill – reach for the brand proven for over 75 years

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Cataclean 2-Pack – Value for Two Treatments

This Cataclean 2-pack gives you two 16-ounce bottles, offering a convenient way to treat your vehicle twice or share with a friend. Each bottle uses the same proven formula that lowers total hydrocarbon emissions by up to 50 percent. It reduces carbon buildup in catalytic converters, oxygen sensors, fuel injectors, and cylinder heads, leading to improved fuel efficiency and overall performance.

It’s safe for gasoline, diesel, hybrid, and flex-fuel vehicles, making it a versatile option for households with multiple cars. The cleaner helps resolve drivability issues like power reduction, hesitation, rough idle, hard starts, and lost fuel economy. Using both bottles over two tankfuls can provide a deeper clean for heavily carbonized systems.

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• Using Cataclean can lower your total hydrocarbon emissions by up to 50 percent
• Reduces carbon build-up in catalytic converter, oxygen sensors, fuel injectors and cylinder heads which results in improved fuel efficiency
• Improves overall vehicle performance-including drivability issues such as power reduction, hesitation, rough idle, hard starts and lost fuel economy
• Safe for gasoline, diesel, hybrid and flex-fuel vehicles; does not alter fuel
• Not for use in 2-stroke or oil/gas mix engines

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Rislone 4744 DPF Clean – Diesel Exhaust Specialist

Rislone’s 4744 DPF Clean is a 16.9-ounce diesel-specific cleaner that targets the entire emissions and exhaust system, including DOC catalytic converters, DPF particulate filters, and SCR selective catalytic reduction systems. It increases power, performance, and mileage while saving fuel. Regular use every 5,000 miles helps prevent excessive exhaust regeneration and clears codes like P2463.

This formula works with all ULSD, regular diesel, off-road diesel, and biodiesel blends B2, B5, and B20. It’s safe for direct-injected and common-rail diesel engines and won’t void your manufacturer’s warranty. Simply add it to your fuel tank and drive normally; the cleaner works through the system to dissolve soot and ash buildup.

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• Increases power, performance, mileage and saves fuel by not only cleaning the entire emissions & exhaust system, but the fuel system too.
• Regular use every 5,000 miles tunes-up the fuel, emissions and exhaust system keeping clean and prevents excessive exhaust regeneration and the CEL light from returning. Clears P242F & Other OBD Codes.
• Will not void manufacturer’s new vehicle warranty. Specifically designed and safe to use on vehicles with DOC catalytic converters, DPF particulate filters, SCR selective catalytic reduction devices, or DEF systems.
• Works with all ULSD (Ultra Low Sulfur Diesel), regular diesel–off road for USA, biodiesel blends B2, B5, B20, DI (Direct Injected), common rail – another name for DI, IDI (Indirect Injected), TDI (Turbo Direct Injected), and turbocharged engines.
• Lowers ignition temperature inside DPF to burn soot and particulate matter, ideal for infrequent highway regeneration intervals.

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Buyer’s Guide: What to Consider

Choosing the right exhaust system cleaner depends on your vehicle type, driving habits, and specific issues. Here are five key factors to consider before buying.

• Engine Type Compatibility: Choose a cleaner formulated for your engine: gasoline, diesel, hybrid, or flex-fuel. Using the wrong type can damage components.
• Treatment Frequency: Some cleaners are for one-time use before an emissions test, while others are designed for regular maintenance every 3,000 to 5,000 miles.
• Target Components: Look for cleaners that address catalytic converters, oxygen sensors, fuel injectors, and cylinder heads for comprehensive system cleaning.
• Check Engine Light Codes: If you have a specific code like P0420 or P2463, choose a cleaner that explicitly targets those issues to resolve the light.
• Ease of Use: Most cleaners require adding to a low fuel tank and driving for a set time. Some come in multi-packs for convenience or deeper cleaning.

Conclusion

Whether you need to pass an emissions test, restore lost power, or maintain a diesel DPF, there’s a cleaner tailored to your needs. Cataclean offers reliable gasoline solutions, while Rislone provides excellent preventive care and diesel-specific formulas.

For most gasoline vehicles, the standard Cataclean is a proven choice. If you drive a diesel, the Rislone DPF Clean is your best bet. Regular use every few thousand miles can keep your exhaust system running smoothly and save you from costly repairs.