02 sensor question

[WDoherty]

This isn't for my lexus, but you guys are so good i figured i'd ask. My other DD is a 77 celica gt. It has a webber carb on it and i want to fine tune it. I will be adding an o2 sensor and an air/fuel meter for tuning. I will be getting an 02 cheap on ebay NOS, but not designed for the car. I can go either 1 wire or 4 wire, the air/fuel ratio meter works with both. My question is, is it really worth the trouble to wire in the 4 wire just to get an 02 heater and the complexity of trying to figure out what wire does what on the 02 sensor (i wouldn't even know how to figure it out) or would a simple 1 wire 02 be fine for my needs, both are cheap so cost isn't really an issue.

 

[Zuffen]

Get the sigle wire.

It will do what you want without the stress of the 4 wire.

 

[WDoherty]

thanks man

 

[gloverman]

I think it depends on where you plan to mount it. If it is close to the Engine where it is hot then a single wire will be fine. If you have long extractors then the heated unit will work better. Remember that narrow band sensors are only accurate at 14.7/14.8 .1 A wideband is far better but more expensive. I have tuned heaps of cars with a narrowband with good success but also do a final check with a dyno. Cheers

 

[WDoherty]

thanks, i will be mounting it close to the engine before the cat, so 1 wire it is.

 

[Peewee]

If its more than say 18" from the exhaust port, the o2 sensor will be too cold under cruise to read correctly.

 

[WDoherty]

so basically i need to mount it right under the exhuast manifold and i should be ok?

 

[Shuey]

Narrow Band or Wide Band?

Hey Guys,

For the record, is the O2 Sensor in a Crown 1UZ a narrow band or wide band O2 sensor?

Regards,

Shuey

 

[-Nemesis-]

Narrow, most factory systems are.

 

[Shuey]

Cheers mate...

 

[hrforever]

4 wire o2 sensor question

I have a 95 Soarer 1UZ with standard manifolds that has 4 wire O2 sensors that have 2 black, 1 white and 1 blue wire going to the motors original loom. The replacement universal sensors have 2 white (heater wires), 1 grey (earth) and 1 black (ecu signal).

Question is, which of the original sensor wires are heater, earth and ecu????

 

[hrforever]

Ok, I have followed the wiring diagram as shown in the Tech area for the 96 Soarer and have discovered the following wiring requirements for each 4 wire O2 sensor.

One wire goes to the EFI relay, one to the ECU Heater plug, One to the ECU O2 reader and the final wire to earth.

So, based on the after markets wiring requirements, I would guess the following;
1. wires for EFI relay and ECU heater plug - connect to 2 white heater wires
2. ECU O2 reader - connect to black ECU signal
3. Earth - connect to grey earth

Can anyone confirm I'm on the right track?