2003 Toyota Corolla Q&A

2003 Toyota Corolla Question: Check Engine Light

Check engine light comes on and code reads catalyst efficiency below threshold clear code and Check engine light comes back on after some time. What is the remedy to get threshold above catalyst efficiency to keep Check engine light off permanately. -
Answer 1
the catalytic converter will most likely need to be replaced, although, a faulty oxygen sensor can sometimes give false catalytic converter codes. -
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