Which Bank is Bank 1 ??

[Greg T]

97 seville northstar. I have an error code that points to bank1 sensor 2. I think this points to the sensor just ahead of the convertor, but which side of the car??

 

[fordtechguru]

bank 1 refers to the side of the engine where number 1 cylinder is, sensor 2 is the downstream or behind the cat sensor, also called a cat monitor sensor..
should be the side closest to the firewall i believe...anyone...

 

[Greg T]

Strange. I finally had a chance to look under the car and it only has one cat. There are only 4 02 sensors. One in each manifold, one before the cat and one after. The number 2 sensor point to the one in front of the cat. The only thing I can figure is that this is a dual purpose sensor. Looks like it feeds info from both banks. I dont get it.