I had a code pop up today, P0420. Its on my 2003 Dodge Ram 1500 with the 5.9L. I have just about 102,000 miles on the truck.

P0420 (M) 1/1 Catalytic Converter Efficiency Catalyst 1/1 efficiency below required level.

I have heard that it could be the Cat itself or the downstream O2 sensor. I was just wondering if anyone has had this or what they did to troubleshoot this code.

Im on a limited budget, so if I buy the 80$ O2 sensor I want it to work. And a Catalytic Converter costs around 80$, or so ive been told.

Thanks in advance.

EDIT: i did hit the 0 one too many times

 

Well I can promise a Cat isnt going to cost 800 bux. P/N 99205HM from Autozone is 80. So maybe you put too manu zeros in there, IDK

I can get you the code info from Alldata later tonight when I get home.

 

Yeah even the highflow performance cats are only $80 so there is no way that your cats is going to be $800... unless you are talking about the fine for not having one on lol then you are looking a little more than that...