P0420 Chevrolet - s10

Question

Had this code, changed my manifold (1 month ago, had a pretty bad crack), and cat (1 year ago, needed replacing), but never changed the o2 sensors, got this code of p0420.... should I change the o2 sensors?

Answer 1

HI there,

Changing the rear O2 sensor could resolve the issue. However you might also want to try a different gas station. Sometimes the fuel additives they put in the gas can cause issues as well. Finally if you used an aftermarket converter it might cause the problem as well.