pantz28

Ok, so I just bought my z a couple months ago. I ordered my o2 sims because it already had mac mids on it. I installed the o2 sims yesterday (which I must of F'd up) and the car seems like it's misfiring at any speed and in any gear. I know there's front and rear o2 sensors. I think I got it right, but if I did, it wouldn't be running like a$$. Can somebody help a brotha out here. I'm about to go out on my lunch break and disconnect them altogether until I figure this $hit out. Thanks in advance.

gwj

I'm not sure how it could go wrong. The sims plug into the same places the rear O2s would plug in. If you plugged them into the front O2 harness(s) (up by the engine) then they are in the wrong place.

gwj

Seems I remember at least one of the rear O2 harness was a bitch to get to as one or both are routed over the transmission-at least on an A4. Hope this helps.

pantz28

Ok, then I am freaking retarded. How far back are the rear sensors? I put mine right where the headers drop down. So I'm guessing that I replaced the front. So hopefully I can get under the car in the freakin parking garage, cause I really don't wanna drive home like I drove to work.

pantz28

ok, i had a 15 minute break and i went down and got under the car in my work clothes to plug the o2 sensors back in. Running good now. But I still need to know the locations of the rear o2's. I couldn't see it when i was down there. how far back are they?

'Trust'

iTrader: (24)

Yea sounds like you put them up front, the rears should be somewhere under where the front seats are, did you have a service engine light on that prompted you to put o2 sims on?

pantz28

Well, when I got my car from the dealer. They knew the cats were removed (legal in florida) and that was why. But here's the thing. I put the sims on, then reset the pcm, and the ses light went away. But when I removed the sims again, the light never came back on, so i'm wondering why it was on in the first place.

'Trust'

iTrader: (24)

The SES light will come back on after awhile of driving again unless you have the sims on or the o2's tuned out, as long as the REAR sims are unplugged the only thing it will do is throw a code, it wont affect how the car runs, thats the fronts, the o2 sims are just to make people happy so the ses light goes off, reseting the pcm will reset any code that has been thrown, so you may have had more than a o2 code, the computer will store a code in history and shut off the light if you reset the pcm long enough, but i havent heard of it doing it w/an o2 code, i'd take it to autozone or whereever to get the code read next time

pantz28

Alright, on the way home, my SES

pantz28

Alright, on the way home, my SES light came back on, so oddly enough, that's a good thing. So, I will find where I need to hook them up, get my ngk tr55s and wires in, and see what happens. I HAVE to get a tune soon as well. Thanks.

gwj

Best I remember (A4 trans,anyway) the wires for the rear O2s come over the trans. When the headers were installed the wires were probably tucked up on top the tranny somewhere, you'll need to put the front on ramps so you can get up under there and search for them. I vaguely remember using zip ties to tie the sims/wires off somewhere at the back/top of the trans.
The end of the harness/rear O2 plug-ins are exactly like the front O2s.
The stock location of the rear O2s is back aways on the Y pipe.
I know it's a bitch trying to get your hand up over the trans to search for the wires, on an A4 anyway.

'Trust'

iTrader: (24)

Yea they are back by the tranny, look around the sides of it if you get it on ramps and i bet you'll see them or at least the connector in the middle of the wire, i zip tied mine to the tranny cooler lines on the passenger side, and tucked it behind the heat sheild thats on the body of the car on the driver side

gwj

Any luck yet?

pantz28

I have to get the car up again. i just finally got the plugs and wires in. I'm gonna get the o2s in this weekend, and hopefully i'll have enough money for a tune and xmas presents. i'll ya posted

snksknr

removing cats is not legal in any state, we just dont have emission tests in florida. If u get busted u will pay a hefty fine, trust me