What are the symptoms of a clogged catalytic converter?
2 Answers
Symptoms of a clogged catalytic converter can be divided into three stages based on severity: 1. Mild clogging stage: Chemical complexes adsorb onto the catalyst surface, manifesting only as reduced exhaust purification function and exceeding emission standards. Colored smoke from the exhaust pipe is often visible; 2. Moderate clogging stage: Chemical complexes have accumulated to a certain extent on the catalyst surface. At this stage, exhaust backpressure increases, fuel consumption rises, and power decreases. The engine warning light typically illuminates; 3. Severe clogging stage: Due to significant blockage, the catalytic converter's operating temperature increases. This stage shows severe power loss, frequent stalling, and in extreme cases, a glowing red exhaust pipe, abnormal noises, and foul exhaust odors.
I've driven several cars and sometimes encountered clogged catalytic converter issues, with very noticeable symptoms. The power drops sharply, acceleration feels sluggish, even climbing a small hill is laborious, like stepping on cotton. Fuel consumption creeps up unnoticed - previously 8 liters per 100km, now exceeding 10 liters. The exhaust sounds abnormal, with sputtering at idle or metallic rattling noises, possibly accompanied by black smoke. The dashboard warning light stays on constantly, especially making overtaking difficult on highways, threatening safety. If not addressed promptly, the engine may overheat and get damaged, causing repair costs to skyrocket. I usually try to use 95-octane fuel and inspect the exhaust system every six months to prevent minor issues from becoming disasters.
