Q: P0420 & PO171
My check engine light has been on for sometime for the codes p0420 & p0171.. When I look online for the codes I'm not sure what I am looking for and it's not really helping me. Went to auto zone they told me it's a sensor went to my mechanic for a second opinion and he says I need a new catalytic converter.. Would like another opinion because I don't want to spending so much that I do not need to spend.. help please thank you..
My car has 122400 miles.
My car has an automatic transmission.
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