[pi55edoff]

I've been having the notorious 301(sometimes 302) code for sometime now. Now I've read a bunch of threads and googled it. One of the possible causes is a bad O2 sensor. This is where I need help. My 00' Sahara does NOT have the California mini cats emissions. So when I talk to my local dealers all they can do is read the parts manual n tell me that there's 4 O2 sensors in it. I only have the two in the exhaust pipe one before and one after the cat. So would the one before the cat still be considered the "upstream" sensor or not?

 

[western196611]

Yes, the one before is called the up stream.

 

[Fatherof2]

You are correct. Those are the same codes mine was throwing. I replaced the upstream and haven't had any problems since.

 

[Jerry Bransford]

Try to confine your search for a replacement 02 sensor to OE Mopar or NTK sensors, avoid Bosch 02 sensors... they don't work well in our TJs.

 

[pi55edoff]

I've already bought an Mopar upstream just made me really nervous cause I had to fight w them that I only had the two. One place asked for VIN #s to assure the right part and another said that didn't matter. Unfortunately I went w the second place cause it was way closer. I asked to see what n where these 4 O2 where n he just printed it out of the service manual. It's the same one I have in my Haynes. Guess I shoulda asked to talk to a mechanic instead of a parts guy. I just felt that I knew a lot more about jeeps than he did. So it was spendy and I'm having a hard time getn her out. My neighbors got a lift n a socket for it so when he's not busy I hope I can get it changed out. Thanks for ur help guys. Makes me feel a little better bout the part