Bank 2 Sensor 2 where is that?

[unknown_owner]

I just had my new converter put on because I the CEL was on and the code was P0421 Warm Up Catalyst Efficiency Below Threshold (Bank 1). So now there is a new code, P0161 O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 2). This one popped up after replacing the rear catalytic converter and the 2 O2 sensors attached to it (thought I should replace them, been driving with that error code for about a year now).

So where is bank 2 sensor 2? Is it on the front cat? that's not one of the new O2 sensors I just put on is it? I thought that before I try and replace the O2 sensor, i would try and clean the MAF sensor, then reset the ECU by removing the battery for an hour then putting it back on. Do you think that would be better?

[wetamup2k3g]

That's the rear downstream sensor, after the rear cat.

[stayer]

This sensor after catalyst for 2 and 3 cylinders. The heater inside the sensor works only when the heating of the motor. After the engine is warmed up, the heater is off. For replacement of the fine universal lambda sensor Bosch LS-07 № 0258986507 - 36Y.

[oakrdrs187]

I think OP is V6. Bank 2 would be one side of the motor, the O2 after the cat on the manifold.

[unknown_owner]

That's the rear downstream sensor, after the rear cat.

Cat be the sensor on the rear cat. I just had the cat replaced and had 2 new O2's put in. I don't think the owner of the shop would have put in a faulty O2.


I think OP is V6. Bank 2 would be one side of the motor, the O2 after the cat on the manifold.

Yeah. it's a v6, so you think it's the one after the cat in the front? I think I can reach that one without a mechanic. Thanks

[wetamup2k3g]

I stand corrected, the even numbered cylinders are bank 2, which are in the front of the car, according to the Haynes manual.

[unknown_owner]

I stand corrected, the even numbered cylinders are bank 2, which are in the front of the car, according to the Haynes manual.

Thanks for the confirmation. That makes me feel better that I didn't get a shaft job done with the rear cat.

[oakrdrs187]

You probably won't get a CEL for the last CAT since there is no O2 after it. A few ways to tell if it is going bad, is poor MPG, loss of power, or a rotten egg smell but you have no CEL.