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brentg454
April 4th, 2007, 07:34 AM
Hey all,

First, the details: 2000 C5 Corvette, headers, Patriot 226 cam, PLX wideband with NB simulation on Bank 2. I am running a stock Vette rear O2 sensor on Bank 1. I am running OLSD (AutoVE process).

I am specifically wondering about whether my O2 voltages are switching properly. If you look at the log file I have attached, it looks like they are hovering at their extremes instead of giving nice up-and-down oscillations like I have seen in other log files. Also, I have noticed multiple times where B2 is giving a voltage slightly higher than 1 ?!? I think it is somehow screwing with my WB output as well. :nixweiss:

I am thinking about pulling the PLX and putting it in a seperate bung for WB only, and putting fresh O2's up front, but I'd like a second opinion before I start moving things around.

I have been doing the AutoVE thing for a while now and I think I am getting pretty close (BEN's +/- 1%), but I need someone to double check my work.

TIA for your input! :)

Brent

Blacky
April 4th, 2007, 09:09 AM
Are you running open loop? If so that will contribute to the lack of switching. In open loop the PCM does not constantly swing the AFR above/below 14.7 so the O2 sensors will not oscillate.

Is O2 sensor 1 a NB simulation from the PLX? If so that *may* explain its laziness. If it is a real O2 sensor, then it is a little lazy and probably needs replacing.

If you are running closed loop and those are real O2 sensors then they are not functioning correctly.

Regards
Paul

Blacky
April 4th, 2007, 09:11 AM
I should read your post more carefully - looks like O2S12 is NB simulation, and you are in open loop.

Put it back into closed look (if you can) and check the function of the O2 sensors then.

Regards
Paul

joecar
April 6th, 2007, 11:43 AM
The NBO2 voltage switching is a function of the PCM doing closed loop feedback using the NBO2 sensor.

brentg454
April 6th, 2007, 12:19 PM
Cool, so it sounds like everything's ok, from what I gather. I am going to put it back into closed loop this weekend to see what happens. Thanks again guys!