Top Signs of a Failing Catalytic Converter: How to Diagnose the Problem

Top Signs of a Failing Catalytic Converter: How to Diagnose the Problem

You’ll find catalytic converters on most modern-day vehicles, but not all of them. Federal law requires catalytic converters for all gasoline-powered vehicles produced after 1974. So, older cars may not have a catalytic converter, but most cars manufactured between 1975 and today will have a catalytic converter as a component of the exhaust system. “Most gasoline cars have catalytic converters to reduce emissions because it’s required by law,” says Lehman. That said, electric vehicles don’t have catalytic converters. Since they don’t run on gasoline, their engines don’t produce harmful emissions. The catalytic converter is a vital component of a vehicle's exhaust system, responsible for reducing harmful emissions. However, over time, it can wear out or become damaged, leading to decreased performance and increased environmental impact. In this article, we will explore several signs that indicate you may need a new catalytic converter.

How does a catalytic converter work?

A catalytic converter’s main function is to convert harmful pollutants from internal combustion engines into less harmful substances. As a result, a catalytic converter reduces a car’s harmful emissions by about 90%, which means less harm to the environment and you. A catalytic converter drastically reduces harmful chemicals you’d be inhaling otherwise.

catalytic converter

The catalytic converter is shaped like a honeycomb and is coated with catalytic materials like platinum, palladium, and rhodium. As exhaust gas passes through the converter, these materials help to convert those pollutants into less harmful substances chemically. The process splits the molecules of unsafe emissions and converts these byproducts of engine combustion into steam. The purpose of a catalytic converter is to turn dangerous matter like carbon monoxide, nitrogen oxide, and hydrocarbons into less harmful alternatives like carbon dioxide and water vapor.

6 Signs Of A Bad Catalytic Converter 

Catalytic converters are an integral part of your vehicle and are essential in controlling emissions. As a car owner it’s critical to keep this vital part in good working order. But how will you know if your car’s converter is having problems?

  • Check Engine Light: One of the most common indicators of catalytic converter issues is the illumination of the check engine light on your vehicle's dashboard. The onboard diagnostic system detects irregularities in the converter's performance and triggers the warning. If the light persists or flashes, it's crucial to have your vehicle inspected by a professional to determine if the catalytic converter needs replacement.
  • Reduced Engine Performance: A failing catalytic converter can negatively affect engine performance. You may notice a decrease in power, sluggish acceleration, or difficulty maintaining speed. This could be due to a clogged or inefficient converter, which restricts the flow of exhaust gases and hampers the engine's efficiency. If you experience these symptoms, it's advisable to have your catalytic converter examined.
  • Unusual Exhaust Smells: A malfunctioning catalytic converter can produce unusual odors from the vehicle's exhaust system. If you detect a strong sulfuric smell, similar to rotten eggs, it may indicate that the converter is not effectively converting hydrogen sulfide into less harmful substances. Such odors are often caused by a deteriorated catalyst within the converter and should be addressed promptly.
  • Increased Emissions: A failing catalytic converter can lead to increased emissions during vehicle inspections or emissions testing. If your vehicle fails to meet local emission standards or emits excessive smoke from the tailpipe, it suggests that the converter is not functioning optimally. Replacing the catalytic converter becomes necessary to ensure compliance with environmental regulations and reduce pollution.
  • Rattling Noises: Damaged or worn-out catalytic converters may produce rattling or metallic noises. This can be an indication of a broken internal substrate or loose components within the converter. The rattling sounds are often more noticeable during acceleration or when driving over bumps. Ignoring these noises can lead to further damage and potential failure of the converter.
  • Fuel Efficiency Decline: A failing catalytic converter can impact fuel efficiency negatively. If you notice a significant decrease in your vehicle's miles per gallon (MPG) despite regular maintenance and driving habits, it could be due to a compromised converter. A clogged or inefficient converter restricts exhaust flow, causing the engine to work harder and consume more fuel.

Catalytic Converter Repair & Replacement

If you have an emissions test performed, you will learn exactly which part of the catalytic converter has failed. Your technician can also perform an analysis of the exhaust gases to identify the fail point. In most cases, the failure results from a thick layer of contaminants on the walls or clogs in your catalytic converter. If the Catalytic Converter is indeed failing you will need to have it replaced at that point to restore your vehicle's low emission status and overall performance. In addition to an increase in harmful emissions, continuing to drive with a faulty Catalytic Converter can result in a loss of power, especially during initial acceleration.

Leave a comment
Translation missing: