where exactly are the O2 sensors on a 1997 ford expedition?

Answer 1

O2 sensors are usually located in the exhaust system, either in the manifold or very close to the catalytic converter. Usually a 2 wire connector.

Answer 2

This vehicle has 4 O2 sensors and two catalytic converters. The Passenger side of the vehicle is bank 1 and the drivers side is bank 2
There are two before the converters and two after the converters.
Bank 1 # 1 before passenger converter
Bank 1 # 2 after passneger converter
Bank 2 # 1 before drivers converter
Bank 2 # 2 after drivers converter

Answer 3

i think its on the passenger side exaust manifold or on the exaust Y pipe before the converter

Answer 4

look at a manual at autozone