QR25, 03 Spec V, install O2 simulator?

[NCSpecV]

I installed my AEBS header this past september. since then, my SES light keeps coming on. I was finally told by AEBS that I needed an O2 simulator for my 2nd O2 sensor. They sent it to me, but with generic directions. I have an 03 Sentra SE R Spec V. Basically all I need to know is exactly where the harness is for the secondary O2 sensor, and if anyone knows exactly how to wire the simulator up? Thanks!

[NISTECH]

well you have 2 connectors mounted to the water tube in front of the engine toward the trans side of the engine one is for your lower o2 and the other is for your upper o2. Now the o2's used to be at the top of the manifold and at the bottom of the cat. both of which are gone probably with your new header. what did you do with the o2's when you installed the header I assume the top one had a hole for it. what did you do with the lower o2? as far as wiring a simulator in I have no idea.

[NCSpecV]

Both O2's are still there. With the AEBS header, you get mounting points for both sensors. It throws the secondary because of the slight temperature difference. Do you have any idea where I might find some more info?

[IveBeenBad]

Do you have access to a service manual? If so, post the wiring diagram for the O2 Sensor and the instructions from the simulator and I will see if I can help you match the schematics

[NISTECH]

Both O2's are still there. With the AEBS header, you get mounting points for both sensors. It throws the secondary because of the slight temperature difference. Do you have any idea where I might find some more info?

If you have a header that doesnt have a cat in it. Its not throwing the code because of tempature its throwing it because both o2's are reading exactly the same voltage changes. the front o2 is suppose to sweep from rich to lean 5 times in ten seconds and the rear should be more constant and only sweep in unison on hard accel [full rich condition] or on decel [full lean condition. Otherwise it should have a very slow voltage change with no cycling from rich to lean. This is due to the cat cleaning up mixture and using the oxygen up to perform its task. Exhaust temp has nothing to do with ECM codes. With one exception and the O2 does not rely on exhaust temps in this case. The ECM will how ever monitier amperage on the heater control part of the o2 just to verify the heater works. If you have a heater code your o2 most likely isnt heating up there for it wont measure oxygen correctly. The internals of the o2 have to be heated to be able to read oxygen. This type of failure would not be a result of your header install but rather a faulty o2 or o2 cicuit. What is your code?

[NCSpecV]

My code is 0420. I got the O2 sensor on, and the SES lights hasn't come back on...yet. I'm going to give it at least a week. Hopefully the directions I got from AEBS were right, and it works. I'll keep you posted. If you have anything else, let me know.

[NISTECH]

po420 is the first description of the code. it is voltage sweeping in unison with the front o2. That is the cat effeciency code. A simulator, like you mentioned, would be the only way to stop the light from coming back on. Good luck hope that works for ya.

[NCSpecV]

Still no light, but I'm keeping my fingers crossed. I'm just tired of resetting the ECU all the time. Regardless of the fact that I've pretty much mastered the technique, and I don't even need a stopwatch anymore, it's just kinda annoying. Thanks.

[NISTECH]

what kind of O2 did you get? a regular one like the factory one or a specially constructed one to compensate for the header?

[NCSpecV]

AEBS sent me one. I believe it's from Kaspar electronics, and it's supposed to be specifically designed for this application. They now include it with the header when you purchase it, but they didn't when I got my 5 months ago.