2000 Mitsubishi Eclipse Q&A

2000 Mitsubishi Eclipse Question: CODE: PO 421

I got a code #421 warm up catalyst below threshold (BANK 1) CAN SOMEONE TELL ME WHAT THAT IS -
Answer 1
It means it is likely that you have a catalytic converter that has stopped being effective and needs replaced. But before you do that -- verify the operation by testing it. The efficiency of a catalytic converter is measured by sensors before and after it. A problem could exist there. -