mechanic says my Toyota Corolla might need a catalytic converter, does this make sense?
Posted by Quick-Chipmunk9530@reddit | askcarguys | View on Reddit | 3 comments
Hey again. I posted here a few days ago because I was nervous about taking my car to a mechanic alone and getting ripped off. A lot of you gave really helpful advice, so I asked them to scan the car before agreeing to anything.
It’s a Toyota Corolla and the check engine light came on. The scan showed: P0420 & P0171.
Service said it might be the catalytic converter, but also mentioned it could be an oxygen sensor or something with air/fuel stuff. I honestly don’t know enough to tell if this is a real issue or if they’re jumping straight to the most expensive repair.
jjack5121@reddit
The O2 sensor is a common item to wear out and results in a check engine light but there are no noticeable performance issues.
Friendly-Inspector71@reddit
Model year, mileage and driving style are important here.
Always driving slowly in a higher gear with short trips can foul a cat in under 100k.
Highway driving with regular maintenance, always getting to operating temperature and it will hold up till the car breaks down.
A P0171 is lean code, so there is problem with fueling that is likely causing issues with the cat and can damage it if not remedied.
ChrisGear101@reddit
Typically a cat goes bad if the car is running very poorly for a good amount of time, or if it has excessive mileage. While it is possible, I'd wager that the odds are low that it is a cat issue.