I just changed my left o2 sensor becuase it was stuck reading 449. After I changed it the new o2 is reading the same (449). Every few seconds it fluctuates to 455 and back to 449. Any ideas??

Chad

 

Hmmm, maybe a break in the wire (pinched or burnt) on the harness (PCM) side that is grounding it out thus the null reading? IIRC (and it has been a while) that is the same reading you will get with the sensor disconnected or likewise grounded out or dead. Maybe you can scrounge up some wiring schematics and trace that wire to the PCM pin and hook up a DMM to ohm the wire. Should also have some voltage and ground going to the sensor too.

Good luck.

 

Ok thanks for the reply I will pull the pcm out tomorrow and shoot the wires to see whats up. I think I can figure it out from the haynes manual.

Chad