Usually bank 2 sensor 1 & 2 are right after the converter in the exhaust pipe.
That would be the passenger side of the engine and it will be the first oxygen sensor that's screewed into the exhaust pipe on that side.
I have a 2004 Silverado 4.3l engine, my questions is are all 4 02 sensors the same are they interchangeable
Unplug the electric connecter and then get a wrench that fits it and take it out of the exhaust pipe.
Bank 2 Sensor 2 is passanger side after cat.
drivers side second one back by transmission
Find cylinder one, usually on the driver side. That is Bank one side, then go to the second O2 sensor, which will be the one after the cat converter.
Oxygen O2 sensor Heater Circuit Malfunction (Bank 1, Sensor 1) Should be drivers side closest to engine.
Bank 1 sensor 1 is the first oxygen sensor usually in the exhaust manifold. Usually it needs to be replaced. Sometimes it can just be a bad connection in the plug for the oxygen sensor.
That is the pre - cat 02 oxygen sensor.
Bank 2 is on the passenger side of the vehicle. Sensor 2 is down stream ( behind ) the catalytic converter. Second sensor from the manifold. May have 4 sensors.
Bank # 1 is the passenger side of the engine Bank # 1 , SENSOR # 1 , is close to the engine in the exhaust Bank # 1 , SENSOR # 2 , is in the exhaust after the catalytic converter ( downstream )
Oxygen sensor bank 2 (pass side) sensor 2 ( after cat) circuit