Misfires and hard idle -04 liberty

[joep]

My 2004 liberty, with 105000 miles, is throwing two codes right now p0300 and p0132, i have also gotten p0420. Since i got her a year ago i have had the O2 sensors replaced twice, a new cat put in, new spark plugs all trying to fix these miss fires and the O2 codes. but nothing works. Any ideas what it could be?

 

[Snail Farmer]

A couple months ago, I fought with the same thing. I spent tons of money replacing things. What it came down to was the O2 sensors. I replaced them the first time and it did nothing to help. Once I installed NTK O2 sensors, it fixed everything. So I would recommend if you didn't replace your O2 sensors with NTK, get some before you waste tons of money like I did. The P0420 code generally means a bad cat. Hopefully it's throwing that code as a result of the O2 sensors. But being the O2 sensors are cheaper, I would definitely go that route first.