o2 sensor position

[Boxersix]

Can someone possibly tell me what 02 sensor is for the left bank(USDM drivers side) and which one is for the right bank(USDM passenger sidE)

Wiring diagrams list them as sensor 1 and 2.

Sensor #1 has wires colored:

Black with White stripe
White with Red stripe
White

Sensor #2 has wires colored:

Black with White stripe
White with Red stripe
Yellow with Blue stripe




I have no original reference for these sensor positions as it's an EG33 in a 2002 Impreza. I'm "thiiiiiiis" close to firing up this beast here

[SoCal LS-L]

Originally Posted by Boxersix

Can someone possibly tell me what 02 sensor is for the left bank(USDM drivers side) and which one is for the right bank(USDM passenger sidE)

Wiring diagrams list them as sensor 1 and 2.

Sensor #1 has wires colored:

Black with White stripe
White with Red stripe
White

Sensor #2 has wires colored:

Black with White stripe
White with Red stripe
Yellow with Blue stripe




I have no original reference for these sensor positions as it's an EG33 in a 2002 Impreza. I'm "thiiiiiiis" close to firing up this beast here

I dont think it matters, both should fit the same harness and work identically.

[Boxersix]

Originally Posted by SoCal LS-L

I dont think it matters, both should fit the same harness and work identically.

If the PCM doesn't have a left/right bank then you're right, but if it uses the O2 sensors to perform running corrective fuel trim per cylinder bank then it's most definitely imperative that they are positioned correctly as you don't want the PCM adjusting fuel trims for the wrong side of the motor.

Essentially if someone could pull back the covering on the harness side of one O2 sensor connector and just look at the wire colors. Basically pull back the loom covering on either side and look to see if the yellow w blue stripe wire in on that side or not(and just let me know what side you checked) I can differ the two sides from just that info

[SoCal LS-L]

Originally Posted by Boxersix

If the PCM doesn't have a left/right bank then you're right, but if it uses the O2 sensors to perform running corrective fuel trim per cylinder bank then it's most definitely imperative that they are positioned correctly as you don't want the PCM adjusting fuel trims for the wrong side of the motor.

Essentially if someone could pull back the covering on the harness side of one O2 sensor connector and just look at the wire colors. Basically pull back the loom covering on either side and look to see if the yellow w blue stripe wire in on that side or not(and just let me know what side you checked) I can differ the two sides from just that info

You mean on your car its possible to plug the right side O2 sensor into the left side harness, and vice versa? On mine theyre pretty well separated left to right, but I guess on an engine swap they could be confusing. Ill go down in a bit and check, unless someone else knows offhand.

[Boxersix]

Originally Posted by SoCal LS-L

You mean on your car its possible to plug the right side O2 sensor into the left side harness, and vice versa? On mine theyre pretty well separated left to right, but I guess on an engine swap they could be confusing. Ill go down in a bit and check, unless someone else knows offhand.

I took an ENTIRE svx electrical harness and weeded out every bit of the harness that was not needed for the motor to run, then wrapped it all back up in a custom fashion. However before removing the harness form the car, I did not label which o2 sensor was right and left. At this point in time either 02 sensor will reach either exhaust header, so it's easy to mix up and thread the wrong sensor into the wrong pipe.

the only difference between the two visually are the signal wires leading up to the female portion of the snap plug. One has a White wire while the other has a yellow wire with a blue stripe. Both have the black/white and white/red wires leading to them(those are the ground and key on 12volt wires)

If you can easily get to the engine harness where the 02 sensors plug in, and roll back some of the wire loom covering you should be able to see the wire colors going into the female part of the clip. You only have to check one side, just let me know what side that was and what the wire colors are and I'll be able to position mine correctly from that


I can assume that sensor #1 is for cylinders 1/3/5 and Sensor #2 is for cylinders 2/4/6, but I want to be 100% positive about it.

thanks!

[SoCal LS-L]

Oxygen sensor 1 is the pass. side one, with the white 3rd wire, Oxygen sensor 2 is the driver side one, with the yellow/blue wire. On mine, the O2 sensor wires were identical to the ones going from the harness. Hope this helps!

[Boxersix]

Originally Posted by SoCal LS-L

Oxygen sensor 1 is the pass. side one, with the white 3rd wire, Oxygen sensor 2 is the driver side one, with the yellow/blue wire. On mine, the O2 sensor wires were identical to the ones going from the harness. Hope this helps!

Awesome, that's the ticket I needed. Thanks a ton!