hello everyone,
quick question I have a 10 caravan with the 3.8ltr and 238xxx miles driving home last night the CEL came on and I have code P0420 active I have read that this is the Catalyst going bad and with this amount of miles I wouldn't doubt it but there is no loss of power. Any thoughts before I start replacing O2 sensors and the catalyst?
much appreciated thanks
daniel

 

I'd start with the sensor first. Obviously the cheaper alternative.

 

I know Bosch is trash but do I need to go to OEM for the sensors?

 

I stick with OEM when it comes to engine management sensors.

 

Agree that O.E.M. sensors are best. The rear O2 sensor is the one that monitors catalyst performance. Considering the mileage I would replace both upstream and downstream sensors. With a cold engine you could physically hit the converter to see if it rattles indicating a broken up catalyst. If not just clear the fault and see if it returns. That being said catalytic converters don't die they are murdered by another problem. Aftermarket catalytic converters are a whole other story.

 

I would start with just resetting the code. Many times they reset and don't return.