Bad o2 sensor?

[boostmaster]

what does an O2 sensor do when it goes bad? Does it just read less volts? mine usually reads .80 at WOT and i'm not lean by the EGTs and i have no knock. I also getting really crappy gas milege... I guess what i'm asking is will repalcing this O2 sensor help anything? If it is reading .80 at WOT is the computer adding fuel on top of the AFC? Am I just really confused. I'm planning on getting my car tuned and I just want to make sure everything goes smoothly so I'm considering buying this o2 sensor and an FPR that I dont have yet...Is this nessessary or can i do it later.

sorry so many Qs-
Blake

 

[dsm10sec]

No, there's no reason to mr. "JDM" motor (profile). If your o2 sensor is out the car would tell you and when mine died it read 1v every second.

 

[91talontsifwd]

I don't think that there is anything wrong with your o2 sensor. Is it cycling and everything else that it is supposed to when you are not WOT? I know that my car seems to run best when the o2 voltage is ~.78-.80v. every narrowband o2 sensor reads differently, so you really cant compare your results with anyone else's. and yes, i would highly recommend getting an afpr if you are running a bigger fuel pump. hope this helps.

 

[cfisher]

I've just pulled a CEL for my 2nd o2 sensor by the cat. It just sticks on 1.24v. Is this necessary to even have since I have a turbo back. I was thinking of just getting a wideband in it's place but for now can I just cut the line.

 

[boostmaster]

No, there's no reason to mr. "JDM" motor (profile). If your o2 sensor is out the car would tell you and when mine died it read 1v every second.

thanx for the reply... mr.-always point out nubie has "JDM" in his profile-- I took "red top" and everything that refers to "JDM" out of my profile so U will quit busting my chops about it ... I really did'nt think much about it when I put it in there, I just thought it was worth mentioning since i waited months for it to get through customs and homeland security. I know its just a joke, but come on...I'm really not that "everything JDM" guy ...btw: i honestly do appreciate ur help though

 

[elementalwindx]

With DSMLink I was able to tell when my o2 sensor was on the verge of dying. It was working and not working like in weird ways, but you could tell because of the data logs. I replaced my front o2 for 89$ and all my knock problems went away