What is PO 421 on a 2002 Eclpise?

Question

2.4 liter engine, 2002 Mitubishi eclipse with a code of PO 421 displaying? What is it?

Answer 1

Hi there,

This code refers to the front catalytic converter that is bolted to the exhaust manifold. This is also referred to as the pre cat or warm up converter. This code indicates it needs to be replaced.