The o2 sensor plug is above where the tranny meets the block. just follow the wire and unplug it much easier than resoldering things.

If you have the o2 housing off why can't you just remove the o2 sensor? If the wires are binding up then just spin off the o2 housing.

When I was taking the o2 sensor off the cat-back, mine was so rusted I had to just cut it off... Its kind of hard to solder the wires (at least on the back o2 sensor) becuase they are this brushy kind of wire...Its kind of like trying to solder two toothbrushes together... So I put male/female connectors and then used electric tape to cover up the connections... But, my sensor still works from when I cut it off so, Yes you can do it, but it will be a lot easier if you can get it out without cutting the wires.

or unplug it right under the thermostat housing

I tired to unplug it, but I can't see anything in there the coolant hose is just too big and fat. I did actually unplug it from the rest of the the wiring but it was bolted to the head somehow and I didn't want to mess with it and I was tired/cranky so I just snipped the wires coming off the o2 sensor.


So I resoldered the wires after using my bench vice to get the o2 sensor out of the housing. Problem is, there were 2 black wires, a blue and a white. You can see my dilema.
I made an educated guess and now that I've gotten everything back together I recieved 2 codes, p0130 and p0135. Both pertain to the o2 sensor but niether were very informative. One was for the heater though.

Do you think I put the wrong 2 black wires together?

On the logger it shows this:
(this was all done sitting in my garage btw)

o2 sensor 1 bank 1: 0.06v CONSTANT, no movement no matter how much throttle is given.
o2 sensor 2 bank 1: 0.96v at idle and will fluctuate in the high .80's and .90's and when I let off the gas and then it drops down to .02v and then rockets back up to a constant .96v

What do you guys think?

I had the same problem, I didn't know which black wire was which... I used my logger to tell which one was which... I'm pretty sure that you won't even get a signal from the sensor if the wrong wires are soldered together... (I didn't) I get the same o2 readings as you... I think the readings from sensor 2 are just higher becuase I have no cat now...

So you think my readings are fine then? What should each sensor voltage be at a given time?
Whats with the codes if thats the case? Does pb blaster harm the heater/sensor?
What is the labeling scheme in pocketlogger for the o2 sensors, is the front o2 called "o2 sensor 2 bank1"?

I used to know exactly which bank was what and what the voltages were supposed to be at a given time but that knowledge has been pushed aside by anatomy and biology homework.

If anyone can clear that up for me too that would be fantastic (codes and voltages, not the homework).

I stumbled upon this as well.
http://www.dsmtuners.com/forums/showthread.php?t=245283

This seems to indicate that my o2 sensor is indeed fecked, becuase it does not cycle at idle and remains constant, unless the throttle is blipped.
Would anyone else agree?

Interesting how there are about 7 o2 sensor threads going at the same time.. must be that time of year.

Well when I tried the two black wires, when I connected them one way, the sensor wasnt reading at all, there was just a blank spot in my datalogger... That's why i thought I wired it back correctly becuase when I switched the black wires, I started getting a voltage reading...

i dont understand why its hard to find the o2 plug.

just follow the wires back to the side (passenger) of the head.
it unclips off the head/block and you just take the two connecters apart like you would for your MAS.

but it sounds like your sensor is fu(ked so cut it, follow wires back, install new one with anti-seize.

mini zilo said:

Well when I tried the two black wires, when I connected them one way, the sensor wasnt reading at all, there was just a blank spot in my datalogger... That's why i thought I wired it back correctly becuase when I switched the black wires, I started getting a voltage reading...

Click to expand...

I can't explain your experiences because in that link I posted above, it was indicated that the 2 black wires were for the heater only, and that it wouldn't really matter which one went to which. Especially since the wires responsible for the o2 sensor function are only the blue and white.

siceclipse said:

i dont understand why its hard to find the o2 plug.

just follow the wires back to the side (passenger) of the head.
it unclips off the head/block and you just take the two connecters apart like you would for your MAS.

but it sounds like your sensor is fu(ked so cut it, follow wires back, install new one with anti-seize.

Click to expand...

Never had a problem finding it...it's on the end of a pigtail like you said you just trace it.
I was just frustrated and I couldn't see how it detaches because of poor lighting/obstacles and I'm extremely handy with a soldering iron so it was only a 5min job to re-connect the wires.

It does sound like its messed up though, either pb blaster slayed it or I was too rough with it maybe.
I've already ordered a new Denso unit for $61 shipped.

I mean it IS supposed to cycle at idle right?

oh most definitly

PieEyedPiper said:

I have the manifold off, the o2 housing off, but now I'm tethered to the car via the o2 sensor wiring. Has anyone just cut the 4 wires and re-soldered them together again afterwards?

Click to expand...

I did that. Worked fine. Tomas.