Heated O2 sensor retro-fit (3-wire)

[devinwalterbmx]

Hey I've heard something about retro-fitting from the one wire non-heated O2 sensor to the Heated 3-wire on my headers... any info on this is it worth it? Heard it makes it easier to tune and idle better? Thanks for the help! Devin

[Eagle-Mark]

It's a good idea and works well. Not always needed but does help to get into and stay in closed loop faster and longer.

Really not that hard to do, just need heated O2 sensor of course wired into a relay for power when key on. No rocket sceience needed...

[91chevZ71]

defintely will make you go into closed loop faster. I went from a 1 wire to a 3 wire and I noticed it going into CL very fast. I grounded the heater wire to the frame, then later moved it to the thermostat housing stud.

If you're considering extending the signal wire to the computer (from the sensor itself), I would check into the actual composition of the wire. I remember reading something about how GM used special material in that wire because they were trying to cut down on signal degradation.

[devinwalterbmx]

So the sensor wire goes to the factory connector, then run a ground, and power (heated) wire to a relay rom the ignition?

[Eagle-Mark]

defintely will make you go into closed loop faster. I went from a 1 wire to a 3 wire and I noticed it going into CL very fast. I grounded the heater wire to the frame, then later moved it to the thermostat housing stud.

If you're considering extending the signal wire to the computer (from the sensor itself), I would check into the actual composition of the wire. I remember reading something about how GM used special material in that wire because they were trying to cut down on signal degradation. Wire to O2 sensor is nothing specail. The wire your talking about is the wires to TBI injectors. There's also an issue with VSS signal and the wires need to be a twisted pair.


So the sensor wire goes to the factory connector, then run a ground, and power (heated) wire to a relay rom the ignition?Yup! Just get power from somewhere like distribution block or off battery to relay, then to heater side of O2 sensor, ground like mentioned above is much better to block like mentioned above, that another long subject, just ground to block. Does not take much key on poower to trigger relay so just about anything key on will work. Poof! Your done.

I've seen some kits with three wire plug that fits new heated O2 sensor and relay wiring on evilBay... think I saw the three wire connector on EFI connection. But you can buy the connector and relay from any parts store. No rocket sceince, pretty simple project.

[91chevZ71]

yah, twisted pairs are like that for a reason. you sure it was injector wires? I don't remember.

ya man, easy project.

[gregs78cam]

This upgrade is on the list for the Camaro, when I put the NBO2 back in it. When I have time.

Wire material? yes regular copper stranded wire, however, I did do some work on a 90s 300ZX and the O2 sensor wires were stranded stainless wire, I remember because we needed to lengthen them and could not solder to them. I think I still have one of them runnin around somewhere.

[Eagle-Mark]

yah, twisted pairs are like that for a reason. you sure it was injector wires? I don't remember. Yup, I have rewired so many stock harness for conversions. All the wires are just regular wire. But when you look at the wires to and from injectors they are differant. I don't know what the technical difference is but they are visually differant and I have never changed what they did. Have shortend them no issues...

[devinwalterbmx]

awesome thanks for all the help! and when I go to get the HO2 sensor from the parts store do you know what year those came in? 96-99 trucks? or do I have to go newer? Again thanks for all the help!

[Eagle-Mark]

Bosch part number 13077

[devinwalterbmx]

Eagle-Mark is the man!

[devinwalterbmx]

Should I install this in my header and after the Y-pipe? I ordered an O2 bung so I can drill anywhere for it. I think that the factory sensor was on the left (Drivers) side after the manifold but since i will be running long tubes I wasn't sure where to put it. I can put it in the header but I wasn't sure if it made more sense to put it in the Y-pipe after it has been thought both banks??

Thanks for all the Help!
-Devin

[Eagle-Mark]

Man I'm not sure that would work even with a heated O2. Way far back would cool to quickly, breaks all the rules for O2 sensor mounting. I would just put it in collector (piece that bolts to header for exhaust to mount to) or just after collector, I have done this and works fine getting a blend of all four cylinders. Better then in header where it picks up more of one cylinder.

Also did one on each side to see if there was any differences after a tune... was a waste of time.

My LT1 engine comes with heated O2 in both sides, but it is Sequentail Fuel Injection.

[devinwalterbmx]

Awesome well I'll just put one in the collector thanks!