p0420-warm up catalyst efficiency below threshold

Question

80000 miles and does not have any leaks in the exhaust system what should I do replace the catalyst or the oxigen sensors

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Answer 1

there is no fuse for the oxygen sensor to check or replace, you can try to use 91 octane from shell with a good fuel system cleaner and maybe do an intake flush and reset the code. Small percent it will work, if it does not work the catalytic converter will need to be replaced