Hi, I have had the engine light going on and off for a while now. I went and bought a ODB2 code reader, and it tells me the following:

P0158 - (Generic) 02 Circuit high volatage (Bank 2, sensor 2)

and

P0440 (Generic) Evaporative Emission System

It would make sense to me that if an O2 sensor was failing, that it would give the Emission System fault with the other code, so I am not too worried about that one. I am just wondering if there is a simple way to tell if the sensor is to blame for the reading, or if the sensor is fine, and the catalytic converter is not working correctly anymore?

I was thinking of switching the post-cat O2 sensors around and seeing if that changes the error code to Bank 1. I assume that if the problem follows the sensor, it is the problem, it the code remains as bank 2, then I know its the converter. Does this seem like a good way to go about this, or is there an easier way?

Also, Last weekend after clearing the codes, I was driving and the car seemed to completely lack power, it struggled to get up to 30MPH, then the engine light started flashing, so I pulled over and shut it off. The temp was fine, no leaking fluids, all the fluid levels were good. So I restarted it and it ran fine. It definatley had me worried, but has run fine all week. Any idea what that was all about?

Sorry for the long post, and thanks for any help, this is my first Chrysler, and I am not too familiar with its common issues.

 

Sounds like the catalytic converter is bad. I had an issue with the 0420 & 0440 code in my 300M. Was able to fix mine & get rid of codes by doing the $6 fix with the spark plug de-fouler. In your case, it seems like you have an issue with your converter. I was told on another forum that lack of power is definitely a symptom of a bad cat converter. Hope this helps.