installed 3-wire o2
Thread Starter
Drifting
Joined: Feb 2004
Posts: 1,485
Likes: 2
From: Champaign, IL
St. Jude Donor '05
project update!
Ok I've picked up my new o2 sensors and wiring harnesses and there are 4 wires not three. Which wire is for what? I have a 92 so I need to put in two, one on each side.
Thread Starter
Drifting
Joined: Feb 2004
Posts: 1,485
Likes: 2
From: Champaign, IL
St. Jude Donor '05
whoops here it is I found it in another post ... so why do they call these three wire o2's when there are four wires?
I've got the diagram too I just need to know which color wire is which and where can I pick up one of these relays ... at Radio Shack? Or do I need to use the relay if I'm going to use the wire from the one to four ... 
Originally Posted by VictorRussell'92
The relay you need is a 12v power source which emits a switched 20amp source. It will have 4 input wires. Once you see the diagram this will be easier. The first wire comes from your fuel pump turn on lead. I can direct you which one to use I just need my car in front of me. The other 2 are the negative and positive 12 volt source. I'm sure you know where to find these. and the last will be the new hot wire to the O2 sensors which will also need their own 12v positive and negative.
I would also suggest you get the wiring harness GM sells with the O2 sensors. This will allow you to interchange the new Heated O2 very fast later down the road. I / Nathan can also get you a part number for that.
Its not hard you just need that diagram. I'm really pissed they got rid of that notes section. I had a bunch of good stuff (Part Numbers, etc) in there.
I would also suggest you get the wiring harness GM sells with the O2 sensors. This will allow you to interchange the new Heated O2 very fast later down the road. I / Nathan can also get you a part number for that.
Its not hard you just need that diagram. I'm really pissed they got rid of that notes section. I had a bunch of good stuff (Part Numbers, etc) in there.
Thread Starter
Drifting
Joined: Feb 2004
Posts: 1,485
Likes: 2
From: Champaign, IL
St. Jude Donor '05
I just need to know which color wire is which and where can I pick up one of these relays ... at Radio Shack? Or do I need to use the relay if I'm going to use the wire from the one to four ... ?
Team Owner
Joined: Sep 2003
Posts: 25,295
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From: I'm the walkin dude I can see all of the world...
St. Jude Donor '03
Originally Posted by ToyC4
I just need to know which color wire is which and where can I pick up one of these relays ... at Radio Shack? Or do I need to use the relay if I'm going to use the wire from the one to four ... ?
Try giving him a PM. He always helps me. 
The correct O2's have a dark wire (Ground) and 2 lighter (Same Color) other wires. It doesn't matter which way you hook up these other 2 as long as you have the ground correct. The relay is at Radio Shack. It is a standard relay I beleve it actually says "20 AMP Automotive Relay" on the little package. It has 4 input wires going into it. 1. is a Negative, 2. is a switched 12 volts source in(Fuel pump wire spliced into here), 3. is a 12 volt positive in, 4. 12 volt positive out to O2 sensors. It looks like a little black box about the size of a Golf ball. I have mine hooked up next to the ECM.
I don't know about other years but the 92 the Fuel pump wire off the ECM (were Nathan and I have our spliced) I think is the number 7 wire off the brown connector. I WILL HAVE TO CHECK that before you go splicing stuff. I will look at it tonight to make sure for you.
Last edited by VR'92; Jan 24, 2005 at 10:00 AM.
Thread Starter
Drifting
Joined: Feb 2004
Posts: 1,485
Likes: 2
From: Champaign, IL
St. Jude Donor '05
well dang it! I called superior chev and bought the o2 sensors and wiring harnesses with pigtails for a 96 vette. I thought this was what I needed. hmm I wonder if I can make these work. Thanks for the info on the relay. 
Thread Starter
Drifting
Joined: Feb 2004
Posts: 1,485
Likes: 2
From: Champaign, IL
St. Jude Donor '05
I'm just wondering what's different on the o2 sensors for the 96. If I can figure out what the fourth wire is for ... maybe it's something that doesn't even need to be hooked up ...
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Safety Car
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From: Atlantis
Cruise-In I Veteran
I considered the H02 but didn't need it.
I have long tube headers on my 73 Super Cheyenne TPI ~727 ECM ,with the 02 sensor wayyyy back in the collector.
It goes closed loop very quickly. Been in there for a long time like that.
But I'm standing by for the heated version if it doesn't behave.
I have long tube headers on my 73 Super Cheyenne TPI ~727 ECM ,with the 02 sensor wayyyy back in the collector.
It goes closed loop very quickly. Been in there for a long time like that.
But I'm standing by for the heated version if it doesn't behave.
Team Owner
Joined: Sep 2003
Posts: 25,295
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From: I'm the walkin dude I can see all of the world...
St. Jude Donor '03
Originally Posted by ToyC4
I will do it tonight, sorry.I don't know what you outta do about those O2 sensors. I have no idea what a 4 wire setup does.
