Welcome to the North American Subaru Impreza Owners Club Sunday December 21, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Normally Aspirated Powertrain

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 04-04-2004, 12:34 PM   #1
bigdweeb
Scooby Specialist
 
Member#: 31035
Join Date: Dec 2002
Chapter/Region: NESIC
Location: Boston
Vehicle:
13 Ford Explorer
14 ISM STi

Default rear Oxygen sensor question

I am getting a CEL... pretty sure it's a PO420, but I haven't had it pulled since I changed some stuff around.

Here's what I have: Borla Headers -> RandomTech Cat -> Stromung midpipe -> Prodrive muffler

The rear o2 sensor had to be replaced and my only option at the time was a universal fit Walker rear oxygen sensor. The sensor didn't come with instructions for how to wire a Subaru 4 wire connector, only the old 3 wire style, even though their product guide said it was supposedly the right sensor.

I have been trying to track down the wiring pinouts for the OEM sensor to make sure I wired it up properly but can't seem to find them. I checked my shop manuals and I didn't see a description of the wires. I have been searching all morning but haven't found anything that seems to match what I have.

The stock sensor I have is a Bosch and has A24-A71 057 98010 on it. There are 4 wires on it: 2 white, 1 grey, 1 black. The 2 white should be the heater wires (polarity independent). I am trying to confirm which of the other 2 is ground and which is signal to the ECU.

Anyone out there have a clue?
* Registered users of the site do not see these ads.
bigdweeb is offline   Reply With Quote
Old 04-04-2004, 08:03 PM   #2
gavinl
Scooby Newbie
 
Member#: 57891
Join Date: Mar 2004
Location: Dublin, OH
Vehicle:
2005 9-2x Aero
Black

Default

The grey wire is signal and the black is ground.

If you want to completely bypass the rear O2 sensor I have a bypass that I construct that can do that.
gavinl is offline   Reply With Quote
Old 04-05-2004, 01:48 PM   #3
bigdweeb
Scooby Specialist
 
Member#: 31035
Join Date: Dec 2002
Chapter/Region: NESIC
Location: Boston
Vehicle:
13 Ford Explorer
14 ISM STi

Default

I would rather get the stupid thing working again if possible... it's mostly on sheer principle at this point. What does your bypass entail? Is it similar to the Pony Express MIL Eliminator?

I think I may have made the opposite assumption that the grey wire was the ground due to its position on the sensor. I looks like it comes out of the side instead of the back like the other 3. I think that was the logic I used anyway. I will have to crawl under the car again to see for sure. If I did miswire it, I hope it's not busted from being miswired all this time.
bigdweeb is offline   Reply With Quote
Old 04-05-2004, 10:33 PM   #4
gavinl
Scooby Newbie
 
Member#: 57891
Join Date: Mar 2004
Location: Dublin, OH
Vehicle:
2005 9-2x Aero
Black

Default

Yup, what I rigged is similar to Pony Expresses Mil Eliminator.

Being a 1v signal device, I don't think you'll bust the O2 sensor if wired opposite. Check it out and see if the wires were indeed reversed.
gavinl is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
2007 STi Rear Oxygen Sensor ( O2 Sensor ) Nitro Don Engine/Power/Exhaust 3 02-19-2009 12:49 PM
Replacing rear oxygen sensor Fubaru Service & Maintenance 12 11-03-2005 01:00 AM
Rear Oxygen Sensor for Link? cpu77 Normally Aspirated with bolt-on Forced Induction Powertrain 15 04-11-2003 10:49 AM
W/B Rear Oxygen Sensor feropont Tri-State Area Forum 7 04-08-2003 02:29 AM
P0139 Rear oxygen sensor circuit slow response slin02 Mid West Subaru Owners Club Forum -- MWSOC 3 05-11-2002 03:32 AM


All times are GMT -4. The time now is 11:36 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.