CEL is on, NEED HELP

OK i have a 04 Rodeo 3.2, and So lately my CEL has been coming on and off. I stopped at shucks and ran an OBDII test when it was on and came back as a p0420-Catalytic converter below threshold (Bank 1) The light will come on for a few days and than go off for a few days, what does that mean? Is this something to really worry about it right now? Is there a way to tell which Cat/oxy sensor needs to be replace? any help would be great

Bank 1 is passenger side. Could either be the sensor or cat converter. If its the sensor it would be the one after the cat, those are the ones that check the condition of the cats. Not very common for them to fail though. You could swap the sensors side to side and see if the problem follows.

agreed. swap from one side to the other. their will be a different code for the other side.

...and if it DOESN'T follow, meaning, you get the same code after swapping them, that most likely indicates a bad cat converter.

I have a 04 rodeo too.

so far so good up to now. So, how many O2 sensors does it have?

why so many?

there are 4 of them. one infront of each Cat and one behind each cat.

Awesome guys, thanks for the help, ill try swapping them this weekend and see if that solves the problem.