Well i replaced my rear o2 sensor (sensor 2) today since I kept getting a CEL for it but now i have 2 more CEL's, lucky me.

17524-o2 sensor heater circ. bank 1 sensor 1
17511-o2 sensor heating circ. bank 1 sensor 1, output too low

Now these CEL's only came on when I first started the car so am i looking at a voltage problem or something else?

 

That's saying the heater for your passenger side primary O2 sensor has failed and the sensor isn't getting up to temperature. Try it out anyway by going driving and getting the engine fully warm. Come home, clear the codes, and let it all cool down, then start the car back up and see if the codes come back. If they do, it's gonna be time to change that one too.

 

K thanks for the help Devil. It looks like I'll be replacing the front one as well.

 

Just out of curiosity, have you seen a dip in gas mileage or performance? Do you have excess carbon buildup on the tailpipes? Any of those are going to serve as some confirmation that your primary O2 sensor problems are real. They are the ones that control the air/fuel mix and failures of them result in the car defaulting to a richened mixture that'll cause one or more of those symptoms.

 

I haven't noticed any problems, but I've only driven it for a few miles with the CEL on.

 

Any chance you touched or played with the 1st o2 sensor when you replaced the 2nd sensor? Both plugs sit right next to each other on the fire wall.

 

My thoughts too..