P0420 in 2002 Sodge Durango RT, 5.9. What is the problem?

Question

Engine light came on several times.   Code tested as P0420 on a Dodge Durango RT 4x4., 5.9 engine.  What is my problem and how do I fix it?   Is it the 02 sensor and if so do I replace all 4?   How difficult are they to install?   How much is this sensor??

Answer 1

Hi there,

The code is for the bank 1 catalytic converter. This is the converter on the driver side of the truck. On rare occasions it could be the rear O2 sensor causing the problem, but most often it's the converter itself. If you want to replace one of the sensors, only do the one after the catalytic converter on the driver side.