I've searched here and a few other places about this code (Low Cat Efficiency Bank 2), and most people wind up getting the cat converter replaced under warranty. Mine's an 04 TJ Rubi. I called my local dealership and explained what I knew about the code, and he insisted on charging a diagnostic fee first to 'assess' the problem, rather than replace the cat, and insisted it was going to be an O2 sensor. So I called a VERY reputable dealer here in GA (Jasper Jeep) and the service tech took the time to walk me through what the service department would do first, second, third, and fourth to fix the problem, and said that while yes, typically the Cat will need to be replaced, he suggested a few things to try first.
So I got to playing with things tonight and now I'm dumbfounded. I started by clearing the codes and resetting the PCM as per the instructions in the FAQ. Then I thought I would swap the sensors around and see if it'd throw a different code, but I found out the hard way that all the sensors have slightly different connectors, so that wasn't going to work. I put everything back together the way it was, hooked the battery back up, did the PCM reset procedure (key on, lights on/off, key off), and then took her for a test drive. The check engine light never came back on. I drove about 15 miles, filled up with gas, and drove back, with nary a problem.
If it does throw the code again, should I just go ahead and replace that rearmost O2 sensor first, before taking it in to the dealers service department? If it turns out to be the O2 sensor, it'd be alot cheaper than a couple round trips to Jasper Jeep to have it looked at (hour drive one way). Plus if it's not the O2 sensor, at least I've already replaced it, so the dealer could rule that out as a potential problem and move on toward replacing the cat?
What would ya'll do?
I really hate dealing with dealer service departments because I've had alot of bad experiences with other vehicles. This will be the first time in the three years I've owned the Jeep that I'll have to have a dealer look at it, and I'd much rather do the work myself if possible.
Thanks!
Jeremy
So I got to playing with things tonight and now I'm dumbfounded. I started by clearing the codes and resetting the PCM as per the instructions in the FAQ. Then I thought I would swap the sensors around and see if it'd throw a different code, but I found out the hard way that all the sensors have slightly different connectors, so that wasn't going to work. I put everything back together the way it was, hooked the battery back up, did the PCM reset procedure (key on, lights on/off, key off), and then took her for a test drive. The check engine light never came back on. I drove about 15 miles, filled up with gas, and drove back, with nary a problem.
If it does throw the code again, should I just go ahead and replace that rearmost O2 sensor first, before taking it in to the dealers service department? If it turns out to be the O2 sensor, it'd be alot cheaper than a couple round trips to Jasper Jeep to have it looked at (hour drive one way). Plus if it's not the O2 sensor, at least I've already replaced it, so the dealer could rule that out as a potential problem and move on toward replacing the cat?
What would ya'll do?
I really hate dealing with dealer service departments because I've had alot of bad experiences with other vehicles. This will be the first time in the three years I've owned the Jeep that I'll have to have a dealer look at it, and I'd much rather do the work myself if possible.
Thanks!
Jeremy