Hyundai Repair: Code P0422, oxygen sensors, exhaust leaks

Question
I have a 2000 Hyundai accent 1.5 SOHC,check engine light stays on all the time, what causes that. I replaced both O2 sensors just about two months ago. It has 107000 miles on it.

Thank you,

Roger Virdi

Answer
P0422 means the ECM (Engine Control Module) believes your catalyst efficiency to be low.  If your oxygen sensors are operating normally and you have no exhaust leaks, then you indeed have a catalytic converter problem; you'll need to replace your manifold catalytic converter.