Remove the rubber grommet, and gently pull on the electrical connector until the connection is obtainable from the hole.
Your question said "O2 SENSOR LOCATED AT THE OUTLET END OF CATALYTIC CONVERTER" Are you working on the sensor behind the Cat? Follow the electric cord up to the rubber grommet in the floorbaord. Remove the grommet and gently pull the cord, as show in the pic above.
O2 sensor is locationed at outlet of cat. converter toward rear of car.
1)Are you saying the 4-pin connector is hidden inside a sheet metal cavity,? 2) and is only accessible after you remove rubber plug and pulling O2 cable out of rubber plug hole?
Can 4-pin plastic connector be seen in engine compartment?
i ASKED (3) QUESTIONS TO BE ANSWERED and recevied previous standard reply.
Not acceptable! DO YOU KNOW THE CORRECT ANSWERS??