Datascan questions - O2 Sensor scan

[cbileske]

So i hooked up my laptop to the car, I have noticed that the one marked O2 Sensor cycles quickly from 0 and up (back and forth),
The O2 sensor named O2 sensor Right hand basically sits at a number and barely moves. My guess is that this O2 sensor is pooched. Which one would the Right Hand sensor be? So I replace the correct one.

Thanks

[DarkCaporaL]

Might as well replace both while your at it...if one failed the other one is probably on it's way out also. 02 sensors are part of regular maintenance.

You can get the NGK 24064 which are OE replacements. Around 50$ a pop.

http://forums.gtrcanada.com/gt-r-tech/5496-o2-sensor-compatibility-3.html

[caliber676]

with the car running, backprobe the 02 sensor with a dvom on ac voltage and see if the voltage fluctuates. The sensor should fluctuate from approx. 100mv-900mv on closed loop. Really its best to use a labscope and see the waveform pattern as your supposed to also check the cross counts (fluctuations over and under 450mv) over a 10 second period but those don't come cheap.

[Skym]

Good advice ^^^^.

o2 sensor tends to stop fluctuating quickly when faulty / dirty and is meant to be checked at 40-60,000km and replaced if necessary. RB26 ECU is set at 230mv for lean trigger and 610mv for rich trigger.

From what I can remember, 0mv is very lean, 1000mv is very rich. 450mv is stoich or around 14.6-14.7:1.

[cbileske]

Awesome, thanks.. These are replacements from the ones that came in the car. I didnt realize that the test should be done while the engine is warm. I tested again while warm and they both fluctuate pretty consistant.
Would Fogging oil mess up a O2 Sensor when it is burned off? just curious.
Thanks