It should be the O2 sensor located directly after the catalytic converter.
Downstream ... This is after the Catalyst Converter.
Bank one is usually the left side of the motor and sensor 2 would be the one past the converter.
That would be the sensor after the catalytic converter.
Bank 1 sensor 3 would be the O2 sensor after the catalytic converter.
That should be the sensor located after the catalytic converter.
Bank 1 sensor 1 would be the first sensor on the drivers side exhaust pipe close to the engine. Bank 1 sensor 2 would be the sensor just before the cat converter. Bank 1 sensor 3 would be the sensor just after the cat converter. Bank 2 sensor 1 would be the first sensor on the passenger side exhaust pipe.
The Location Bank is a photo location and film location agency based in Amsterdam but working wordwide for the film photo and advertisement industry.
If that S10 has a 4.3 engine, I find it best to remove the distributor to gain better access to the oil pressure sensor.
Need more info, is this the 4 cylinder or 6 cylinder engine and which sensor on bank 1.
That would be the O2 sensor after the catalytic converter.
Assuming this is a V-6, bank 1 sensor 1 would be the first O2 sensor in the exhaust on the drivers side of the engine.
That should be the O2 sensor just before the catalytic converter.