I recently bought a speed density TPI system that I'm going to be installing this weekend. In calling around to parts stores they only have a one wire O2 sensor for the application, but the harness has a 3 wire connector for the O2 sensor. Is this a modification, or was the 3-wire stock on this applicaiton? Can I use a one wire, or should i try to find a 3-wire?

 

3 wire O2 sensors came on ZR1 Corvettes and should be used if you have headers. The difference is the 3 wire sensors are heated. Try a dealer, someone on here might have the part #.

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'88 IROC TPI 355, '69 truck 4-bolt, fully balanced, 9.75:1 compression, fully ported '70 truck heads(for now), Harland Sharp 1.6 Roller Rockers, Comp Cams CS 252AH-12, ported '86 TPI converted to speed density, Crane AFPR, Flowmaster 3in. exhaust, Edelbrock TES headers, all emissions equipment is still intact, plan on burning my own chips, many more mods and parts on the way as time and money permits =(
Best E.T. with TBI 305: 16.11 @ 82mph
Haven't been to track with new motor
Won bracket races at Numidia Raceway with my '70 Nova
In memory of Dale Earnhardt, I'll miss cheering for that black #3 on raceday!!!

 

Its been modified, all thirdgens have a one-wire O2 sensor. But you should be able to get a 3-wire one by asking for a Corvette ZR1 O2 sensor, like was suggested by IROCZ88. It shouldnt matter what year, 90-95.


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West Coast GM Shootout 2001!
1991 Camaro Z28
5.7L 5-Speed (originally 305)
13.25 @ 107.18 MPH
Southern California
Member: SoCal 3rd Gen F-Bodies
Webmaster: SoCal F-Bodies
-=ICON Motorsports=-

 

Well, right now i have a one wire 02 sensor. Can i use that for now since I still have stock exhaust? And then get a 3 wire when i get a performance exhaust?

 

Yes, actually I think you can. I'm not sure, but I think one wire is power, one is ground, and one goes to the computer. All you need is the one going to the computer but it won't be heated then.

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'88 IROC TPI 355, '69 truck 4-bolt, fully balanced, 9.75:1 compression, fully ported '70 truck heads(for now), Harland Sharp 1.6 Roller Rockers, Comp Cams CS 252AH-12, ported '86 TPI converted to speed density, Crane AFPR, Flowmaster 3in. exhaust, Edelbrock TES headers, all emissions equipment is still intact, plan on burning my own chips, many more mods and parts on the way as time and money permits =(
Best E.T. with TBI 305: 16.11 @ 82mph
Haven't been to track with new motor
If you have any questions on converting from TBI to TPI email me at jdkchevy70@yahoo.com
In memory of Dale Earnhardt, I'll miss cheering for that black #3 on raceday!!!

 

I used a 3 wire setup for my 1986/7 setup. In my opinion, the heated units are a better choice.

Check this part number out ... cheapest heated unit I found.

AC Delco # AFS-74
GM # 25312179

This fit perfectly into my cast iron manifolds. The signal wire (purple) goes to the ECM (if you have a one wire setup) and the two brown wires are for +/- 12 (it's a heating element, so it does not matter about which is which).

The connector is a 3 prong (large round ones, about 1/8" each). If you have this connector on your harness, then this is probably what you need.

I have to think an O2 sensor for a ZR1 would be expensive ... anything for a vette always seems to cost more.

Mark.

 

I think for now I'm going to use the one wire one that is in there. I plan to splice the one pin connector from my current lg4 harness on to the signal pin on the 3 wire connector from the TPI harness I have so it will be able to plug in either type of sensor. Anyone see a problem with doing this as long as i tape up the unused connector so nothing grounds out?

 

Wow that’s impressive. Is the 5.7 motor you put in a stock 350 or is it built? 107.18 MPH is really good. And I didn’t think those Borg Warner 5 speeds could handle the torque on a 5.7 motor?

 

This thread is so old it can almost buy beer.

 

This thread is 6 days older than my daughter whose a Jr. in college

 

And that means what exactly? You can’t talk about the car because you talked mentioned it in a thread years ago? Seriously, it’s dicks like you that shouldn’t be on here!

 

Come on man there’s no reason to get upset about silly words on the internet, of course you can talk about car stuff from a thread from 20 years ago. If your looking for information on a heated 3 wire o2 sensor use the search function you’ll find a crap ton of more up to date threads.
I hope you have a good day bud 💯

 

Millennials are sensitive.

 

I’m 50yrs old & im hardly sensitive or upset at his ******** comment. I can call someone an ******* if they are being one and not get upset at all.

 

MIke I'll be 50 in March myself, somehow, seems like yesterday I was 29 and first dating my wife. Sorry that you took my comment as being an *******, wasn't my intentions, welcome to TGO.

 

That engine at the time was a ported ZZ4 heads, LT4 hot cam, headers, etc. It made 318 RWHP and 419 RWTQ. The T5 blew up when I started running 12's shortly after that.

Go to the TPI forum and look at the sticky post at the top called "quest for a better flowing TPI" for the details.

That car was sold several years ago. Now I have Dyno Don's 1990 Trans Am, and it makes 400 RWHP and 420 RWTQ thru a T56.