2001 O2 Sensors W/Banks manifold

Recently the 01 has been getting a high voltage code on a bank 2. It does't appear to affect running, but it'd be real nice to fix.

The Jeep has a Banks exhaust header and CA Emissions package with 4 O2 Sensors.

I have a simple scanner that will allow me to grab a "snapshot" of the readings, but I don't know what exactly I am looking for. I would like to narrow this to the exact sensor if possible.

I have the FSM and it seems to indicate that Bank 2 is comprised of the sensor before the aft CAT, and the sensor after the aft CAT ( my 01 has 2 CATS. 1 for Cyl 1-3 and the other for 4-6)

My questions are these:
* How can I tell which sensor is to blame.
* The NAPA website indicates 4 separate part numbers for O2 Sensors. Really?
* Could this be caused by a bad exhaust gasket?

Exactly what trouble code or codes do you get ? The code will tell you which sensor.

The code will say something like bank 1 sensor 1 or B1S2. The front 3 cylinders is bank 1, the rear two bank 2. The sensors in the header are sensors #1, and ones after the precats are sensors #2.

Since its Bank two, its the rear 3 cylinders, now to just narrow it down to sensor 1 or 2.

I'll see if I can get to the Jeep tomorrow and pull the exact code.

A bit late, but the code is "P0158 $D1 1/2" In English below it, it reads "O2 Sensor Circuit High Voltage Bank 2, Sensor 2".

Well, given what I read in the FSM and Tayln posted, this is a "Uh, Duh" type of thing. I appreciate the info. It's one thing to have a tool. It's another knowing what to do with it

Anyway, given all that, tonight I threw a board on the garage floor to keep me out of the water, got out my torch (Propane), Penetrating oil, a LED Trouble Lamp, and a 7/8 combo wrench. Heated it, doused it, heated it, pulled on it (Engine moved). Yah, that was a whole lot of nowhere fast. Cut the wires off the sensor, got a 7/8" Deepwell and a 1.5' Bar. Heated the bung for 5 minutes, hit it with oil, pulled on it (Moved slightly), and repeated until the thing was loose.

I don't have one on hand, but I did find a 2.5L pipe with an O2 Sensor in it. I figured that it would either work, or not, and it was free. So I cut and spliced the 01' connector to the 2.5L O2 Sensor and installed it.

So far no codes... I do plan on installing the correct sensor. It's a $ thing.

Congrats on a job well done.

Somebody should alert bimmerjeep, an O2 sensor got changed, and it only took 5 postings and some basic hand tools.

Lol