remove secondary catalytic converter?

2023 NISSAN ALTIMA
63,000 MILES • 2.5L • 4 CYL • 2WD • AUTOMATIC
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CHRISTIANMONRO
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  • 4 POSTS
If I remove what I think is the secondary catalytic converter on my Altima, will it cause engine damage or check engine light? It’s after the two sensors it’s super small. I just wanna know if we’re moving that will cause any damage. i’ve already done a muffler delete and a resonated early. I know there’s two catalytic converters.
Dec 8, 2025 at 9:18 PM
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STRAILER
  • ✓ASE Certified Mechanic
  • 54,832 POSTS
  • ASE Certified Mechanic
Either one of these is safe to delete and will not cause engine problems, as long as there is no sensor behind the one you want to take off. I assume this is a track car correct? If not the car may not pass inspection FYI. Check out the images (below). Let us know if you need anything else.
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Dec 9, 2025 at 11:30 AM
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