Does a Deteriorated Three-Way Catalytic Converter Affect the Car?

[Matilda]

It does not affect the car, but it has a significant impact on the environment. Introduction to the Three-Way Catalytic Converter: It is the most important external purification device installed in the automobile exhaust system, which can convert harmful gases such as CO, HC, and NOx emitted by automobile exhaust into harmless carbon dioxide, water, and nitrogen through oxidation and reduction. Symptoms of a damaged Three-Way Catalytic Converter include: Shortly after the vehicle starts, the exhaust manifold emits a noticeable red burning phenomenon towards the Three-Way Catalytic Converter, and a hissing air leakage and gurgling sound can be heard when accelerating; if the Three-Way Catalytic Converter is damaged, the secondary oxygen sensor will not be able to accurately provide data to the driving computer, and the engine fault light should come on; a pungent, foul odor can be smelled during idling or acceleration.

[LaRachel]

Aging of the catalytic converter absolutely has an impact. I've been running an auto repair shop for over a decade and see this issue frequently. Aging reduces catalytic efficiency, increasing harmful gases in the exhaust, such as carbon monoxide and hydrocarbons, leading to excessive pollutant emissions. Not only does it pollute the environment, but it may also trigger the engine malfunction light. You'll noticeably feel reduced power and sluggish acceleration because exhaust flow is restricted when you press the throttle, creating high backpressure that hampers performance. Fuel consumption will also rise significantly—what used to be 500 km per tank might drop to 450 km, burning through your money faster. The most frustrating part is during annual inspections, where an old catalytic converter often causes excessive emissions, failing the test and forcing you to make an extra trip and replace the part. I recommend regular checks on the catalytic converter's condition—listen for unusual noises or smell for foul exhaust odors. If aging is severe, replace it promptly to avoid causing more issues.

[GarrettFitz]

A deteriorating three-way catalytic converter is no small issue. I often encounter similar situations during my daily commute. When it ages, the converter can become internally clogged or structurally loose. Failing emissions standards is the least of the problems – the car feels sluggish, struggles uphill, and the engine sounds muffled, especially at low speeds. Fuel consumption skyrockets, adding an extra hundred or two to monthly gas expenses, which really hurts the wallet. The repair shop near my home mentioned that a worn-out catalytic converter could also damage the oxygen sensor, making repairs even costlier. What I can do in the meantime is use high-quality gasoline to reduce carbon buildup, and long highway drives can help clean it out. But if I notice pungent exhaust fumes or the check engine light comes on, I get it checked immediately—no delays. Regular maintenance saves money and hassle; don’t wait until you’re stranded on the roadside.

[LaCaden]

I've been environmentally conscious for years, and the aging of three-way catalytic converters has a significant impact. As a key emissions component, aging reduces catalytic efficiency, leading to increased exhaust pollution in urban air. From a personal perspective, the car's power weakens and fuel consumption rises, which is uneconomical. With stricter regulations, older catalytic converters struggle to pass annual inspections, requiring costly replacements if they exceed standards. I recommend driving friends to perform regular maintenance to prevent aging, extend lifespan, save money, and protect the environment.