STFT's still active in open loop?

[mistermike]

Did my first logging run using the widebands today. In preparation I performed the following:

Disable LTFT
Set closed loop temp at upper limit
Forced octane scaler to 100%
Set DFCO enable speed at upper limit

During the logging runs, I noticed that STFT's were still hopping around. Is there something more I need to do to kill them?

After pasting in my BEN's and returning the above settings to normal, my LTFT's are trending a tad high. Not a lot, but enough to get my attention. I'm thinking maybe the STFT's were not allowing the widebands to read the true open loop AFR.

[SinisterSS]

Double check the pdf file I sent you; STFT is in there... :D

[GMPX]

As a developer of the software I am never quite sure what you guys have access to in the latest downloadable cal files, sorry, you think I would, but obviously we are always adding things so I am usually a few steps ahead and I forget where the public version is at, anyway.....I say that because we found the same thing recently when testing the new custom O.S's. There is indeed two modes of open loop.
One that seems to ignore the O2's totally, and another that tries to apply STFT even though you are not in closed loop mode (or commanding 14.63:1!!!).
Do you have parameter {B4206}?.

Cheers,
Ross

[SinisterSS]

No B2406 here and don't have the other one mentioned a week ago or so either.

[GMPX]

I should just keep my mouth shut!!.
Let me match everything up with Paul today and we can upload some upadted cal files.

Cheers,
Ross

[mistermike]

Thanks, Rick. I overlooked the STFT Idle disable in my haste to fire up the widebands! What about off idle? The STFT's were active throughout the range. There are all kinds of STFT parameters in the O2 section, but I don't like to mess with stuff I don't fully understand without advice from someone more experienced. (Dang, what's this purty button do?) BTW, you have a whole list of things to change regarding DFCO. Just pushing the speedo enable to 255 alone won't do it?

Ross, no luck finding B4206. I'm using your O/S #04110001 v1 (2004 GTO). Also, the description section for "B4111: STFT Base Correction at Non-Idle" mentions a B4119, which is also not found.

Cheers,
Mike

[mistermike]

I'm wondering if, in addition to disabling B4108, if zeroing out B4115 through B4118, and zeroing out non idle STFT base correction and/or multipliers will work me around this issue?

I've followed most of the advice posted on the boards except for disabling PE, which theoretically shouldn't be necessary with BEN tuning, and setting the open loop AFR to 13, which is suggested as a "safe start" point on a brand new tune, unless perhaps skewing the AFR like that would prevent the O2's from switching. I really don't get the 13:1 thing. Can you tell I'm new at this?

[mistermike]

Well, after zeroing out the parameters mentioned above, the car would stall, so that one went in the can pretty fast. I decided to try the 13:1 thing, even though I don't fully understand why. Except, instead of going into the tuning tool to make all those changes (did I mention that I'm lazy on weekends?) I simply pulled up the control panel in the scanner and commanded 13:1. Low and behold, the STFT's went to zero! Laziness never interfered with my curiosity so I tried 14.7:1. Aside from commanded AFR PID in the scanner going to 14.78, the STFT's remained dormant. It appears that there is a 0.08 being secretly added to whatever you command in the control panel, so I set 14.6, the scanner indicated 14.68, voila! It appears that commanding ANYTHING in the control panel will kill the STFT's. I haven't tried this with open loop enabled, mind you. Now all I wish for would be a way to minimize the control panel so I don't have to shove it out of the way to see the dashboard or maps. Maybe a flashing nibnoid or thingamajig to remind you it's minimized, but still active. Back to taking a Sawzall to my garage roof until the temperatures drop enough to do some real logging :D