it is the one before the cat converter
in the exhaust manifold
where is the bank1 o2 sensor at and how do i change it please i need your help
The bank 1 sensor 1 oxygen sensor on a 2002 Honda Accord is located on the header. It is right next to the sensor circuit.
Bank one are before the Cat and bank 2 are after the Cat.
Bank two sensor two on a 2002 Ram is passenger side, after the catalyst.
bank 1 sensor 1 2002 on toyots sienna
Bank 2 is the drivers side of the engine in a 2002 Mercury Mountaineer Sensor 2 is after the catalytic converter ( downstream )
Oxygen Sensors are usually in the exaust pipes!
Bank 1 is where cylinder #1 is. Sensor 1 is ahead of the converter (usually in the manifold.
Replace it. Sensor 2 is the one AFTER the catalytic converter.
Oxygen sensor heater malfunction (cylinder bank #2, sensor #1)
It is caused by Bank 2 Sensor 2 oxygen sensor failing.