I recently did the plenum job on the Dodge, I didnt replace the factory o2 sensory. I have been reading and thinking that maybe I should have. I would hate to throw away $70 for nothing, But with a plenum this bad, do you think the sensor is covered in crap?

 

A good scanner should be able to read if the sensors are working right.

 

It should throw a CEL. If you are having any issues with it running strange at all, or would rather just get it out of the way (preventative maintenance?) - might as well just replace it. It's only about $50 and takes 10 minutes.

Part # 23023, NTK.