Glossary
Catalytic Converter
An exhaust component that uses a precious-metal catalyst to convert harmful combustion byproducts into less harmful gases before they reach the tailpipe.
Unburned fuel from a sustained misfire overheats the catalyst and can melt its substrate, which is why efficiency codes like P0420 often trace back to an upstream ignition or fuel problem rather than the converter itself failing on its own.
See also
- Misfire: An engine cylinder that fails to combust properly — from a weak spark, bad fuel delivery, or low compression — causing a rough idle, hesitation, or a flashing check engine light.
Guides that use this term
Comparisons
Guide Type: Comparison
Recalls & Safety
Guide Type: Recall Explainer
Diagnostics & Repair
Guide Type: Default
Diagnostics & Repair
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