What are the Symptoms of a Bad Catalytic Converter?

Published on

March 4, 2024

catalytic converter under a car

Catalytic converters are used in automobiles to reduce emissions of harmful substances such as nitrous oxides, carbon monoxide, and hydrocarbons.

Catalytic converters can fail for many reasons. Every car has a catalytic converter, but when it stops working properly, various symptoms can show up. If you notice any of these symptoms, it's best to take your vehicle to a specialist for inspection.

1. Rattling Noise

Catalytic converters make a sound if they start to fail. It could sound like a loud rattle or like the engine isn't moving as smoothly as it normally does. This can be a sign of an excessive amount of sulfur in the catalytic converter's exhaust system, which can render it ineffective.

2. Blue Emissions

Catalytic converters don't work properly when the combustion process produces large amounts of blue emissions. This could happen when sulfur is continuously being emitted from the unit, preventing its effectiveness from operating efficiently.

3. Reduced Engine Performance

Engine performance will be lower if the catalytic converter is unable to efficiently convert harmful elements before they are released into the environment. A clogged catalytic converter restricts exhaust flow, whereas a cracked catalytic converter leaks harmful gases into the environment. Either fault negatively affects the engine performance, causing a reduction in acceleration and power.

  • Power Loss: A bad catalytic converter can lead to power loss when it fails to balance fuel and airflow. This is due to its inability to reduce harmful emissions in the environment properly.
  • Hesitation: If one of the components inside the catalytic converter is broken, acceleration will be affected due to a decrease in power.

4. Low Gas Mileage

A failing catalytic converter can lead to a decrease in gas mileage since there may be low emissions coming out of your exhaust system or broken cars may produce more fuel consumption than normal.

5. "Check Engine" Light Comes On

The check engine light may illuminate if the oxygen sensor within the catalytic converter becomes clogged or a short circuit causes an error. The check engine light could also turn on if the temperature in the catalytic converter fluctuates.

6. Sulfur Smell from Exhaust

If the catalytic converter is broken, sulfur can come out through your car's exhaust system, leading to a rotten egg-like smell coming from your car's tailpipe.

7. Failed Emissions Test

If the catalytic converter is broken, the engine's computer will fail the emissions test.

The Bottom Line

The catalytic converter can fail for many reasons, and it's vital to diagnose the fault before replacing it. For the catalytic converter to function properly, your car needs to have proper parts such as a computer and sensors that regulate how well the exhaust system functions. If your car is lacking any of these vital components, it will not be able to run effectively with its catalytic converter, and you may notice the symptoms above when your vehicle won't start or perform normally.

The catalytic converter has to be replaced if it deteriorates due to extensive use and it can no longer efficiently convert harmful emissions into the environment. If you need catalytic converter repair, give us a call today!