How do I know if my catalytic converter actually needs replacing?
Check engine lights after using a head gasket sealer leave drivers unsure whether a catalytic converter is ruined or if multiple converters need replacing. This uncertainty makes it difficult to know which parts to service without guessing or wasting money on unnecessary replacements.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Using stop-leak products like Blue Devil
- 2Taking the vehicle to a dealership for factory warranty service
- 3Having the car professionally diagnosed by a technician
- 4using diagnostic apps to read sensor data
- 5asking mechanical advice online
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“I ran the codes and I’m unsure if I should replace the catalytic converter?”source ↗
“i had the engine at 2000rpm. also, if cat is done for good, which one do i need to replace? apparently mine has two? one pretty much at the engine and another down under the car.”source ↗
Where this came up
People with this problem also raised
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