So i used a code reader on my 03 MCS and this is what showed up. It says i need to replace the O2 sensor but what are all of the other error codes that were thrown?

 

Would think that with a O2 sensor on the fritz the ECU is having fits so anything to do with the air/fuel mixture is involved.

 

Agree with r53coop.

My advice would be to replace at least the Bank 1 #1 and #2 sensors, clear the codes then road test the car. What you do next depends upon if the CEL comes on and what error codes are present.

Be sure you handle the new sensors with care. Do not touch the tip. Do not use any anti-seize on the threads. Do be sure you get the electrical wiring lead routed properly so it can't touch the hot exhaust or rub against anything. Be sure the sensor lead snaps completely into the wiring harness connector.

Do not use electrical contact cleaner on the electrical connectors. Some sensors "breathe" (sample outside air) via the wiring harness and connector. Using cleaner can interfere with this and render the sensor bad.