What Impact Does a Damaged Three-Way Catalytic Converter Have on a Vehicle?
2 Answers
A damaged three-way catalytic converter not only significantly increases vehicle fuel consumption, reduces power, and causes exhaust emissions to exceed standards, but in more severe cases, it can cause the exhaust pipe to glow red, leading to vehicle self-ignition. For a long time, auto repair shops have lacked effective preventive measures for aging three-way catalytic converters and have no effective treatment methods. For aging three-way catalytic converters, the only solution is replacement. How to determine the condition of a three-way catalytic converter: Visual inspection. Examine the exterior of the three-way catalytic converter for any damage or discoloration. If there are scratches, cracks, etc., it is likely that the three-way catalytic converter has been damaged. If there are noticeable gray spots in the center of the converter's protective cover, severe discoloration spots on the shell, or purple marks, it may indicate that the three-way catalytic converter has experienced overheating issues. Check the engine's exhaust condition. Place your hand near the tailpipe exhaust outlet to feel the exhaust flow and check if the three-way catalytic converter is clogged or if there are issues with poor exhaust flow. Another method is to open the air filter, remove the filter element, and observe if there is exhaust backflow during rapid acceleration, which would indicate poor exhaust flow in the engine. To assess the condition of the TWC (Three-Way Catalyst), check if the secondary air injection pump is functioning properly. Use an infrared thermometer to determine. Compare the temperature difference before and after the TWC using an infrared thermometer. If the temperature difference between the intake and exhaust ports of the three-way catalytic converter is less than 10°C, the TWC is already damaged.
In my over a decade of driving experience, I've seen quite a few cases of failed catalytic converters with significant impacts. When it fails, my first observation is reduced vehicle power - the throttle response becomes sluggish, especially noticeable when climbing hills. Fuel consumption also skyrockets; while normally achieving 7L/100km on highways, it jumps above 9L after failure. The exhaust emits foul, pungent odors, sometimes with black smoke when idling. Prolonged issues will trigger constant illumination of the engine warning light, causing unstable engine operation and increased carbon buildup risks. Worse still, delayed repairs may lead to exhaust pipe blockage, affecting heat dissipation and potentially damaging internal engine components. I recommend checking the emission system during every maintenance service and addressing abnormalities promptly to prevent minor issues from escalating.