How Often Should the Three-Way Catalytic Converter Be Cleaned?
3 Answers
The three-way catalytic converter should be cleaned approximately every 20,000 to 30,000 kilometers. Its function is to convert harmful gases such as carbon monoxide, hydrocarbons, and nitrogen oxides in vehicle exhaust into harmless carbon dioxide, water, and nitrogen through oxidation and reduction reactions. It is an essential external purification device installed in the vehicle's exhaust system. The method for cleaning the three-way catalytic converter is as follows: 1. Use a lift to raise the vehicle to the normal working height; 2. Remove the three-way catalytic converter from the vehicle; 3. Prepare oxalic acid using specialized maintenance equipment; 4. Soak the three-way catalytic converter in the prepared oxalic acid solution; 5. Rinse off any remaining oxalic acid solution and impurities with clean water.
I often encounter this issue when repairing cars. Whether and how often to clean the three-way catalytic converter really depends on your car's usage environment. If you frequently drive at low speeds in urban areas, carbon buildup and clogging are more likely, so it's recommended to check the exhaust pipe for foul odors or sudden increases in fuel consumption every 20,000-30,000 kilometers. If you do a lot of highway driving, cleaning it every 40,000 kilometers is sufficient. I remember one client who insisted on not cleaning it for 100,000 kilometers, and the catalytic converter got completely clogged, causing exhaust flow issues and triggering engine fault codes—repairing it ended up costing much more. When cleaning, avoid using oxalic acid or other makeshift methods from roadside shops, as they can corrode the ceramic substrate's coating. It's safer to use professional hydrogen-oxygen decarbonization equipment.
Bro, let me tell you, this thing is like the kidneys of a car—it needs regular detox. My modified Civic with aftermarket exhaust tends to accumulate carbon deposits due to insufficient exhaust temperatures, so I use a catalytic converter cleaner in the fuel tank every 15,000 kilometers. If you smell rotten eggs from the exhaust or fail emissions during inspection, you need to address it immediately. A heads-up for fellow car modders: Incorrect air-fuel mixture ratios when tuning the ECU for horsepower gains can seriously damage the catalytic converter. A friend of mine ignored this after a tune, and his converter clogged up in just three months, costing over 2,000 yuan to replace. Also, don’t cheap out on gas—low-quality fuel from shady stations contains lead and phosphorus, which are the real killers of catalytic converters.
