Accord Ex 2001 2.3L OBD code p1164

i have an accord ex 2001 2.3L. The engine light came up and I ran OBD rec'd
-P1164 Air/Fuel Ratio (A/F) Sensor (Sensor 1) Range/Performance Problem
-P1164 Air/Fuel Ratio (AF) Sensor (Sensor 1) Circuit Range/Performance.


Im not clear about the code. is it the o2 sensor in front of the engine or the one on the CAT?

The one in front. The one by the cat would be sensor 2