I think this is what your looking for.
I think this is what your looking for.
I know where to turn the STFT off in open loop....
I'm trying to learn why that is even an option. Read my last post again.
2003 Chevy Silverado Daily Driver, 408 Iron Block,
LS3 Heads/Intake, 231/239 114, 4L80e, Yank SST 3200.
Don't I feel smart.. sorry bout that.
Yep. Time to step back into the shadows and lurk again.
As to why it's an option, who knows. It's oxymoronic in my opinion. I have no idea, perhaps it's some kind of pseudo closed loop for emissions or something. I think Chris talked about that under certain other circumstances. You'd have to ask a GM Powertrain engineer/programmer of that era to know.
All I know is that you do not what them enabled for your tune.
If you could get another log with ETC % added and desired idle RPM pretty much the same as the first one then I think you'll be able to fine tune the issue as I believe the OL STFT is causing most of it.
Secondly, I'd set the min LTIT to 0.00 (and probably max too) because the LTIT once it is triggered (temp usually) is a single cell resolution and because you cannot discriminate between P/N and Gear I do not see the advantage to having LTIT enabled; in fact I can only see the disadvantage. I would also return the STIT range to stock, if it is stock it seems to be only half that of most OS I've seen and given that you need the STIT to pick up the slack I think you need the headroom.
Once the LTIT is zeroed and STFTs disabled in OL you'll need to redo the RAF; you'll likely find a reduction in your RAF especially down low.
Hope that helps
Last edited by SSUte01; 02-09-2012 at 08:01 PM. Reason: Added content
Sounds good. I will fix the tune right now and do a log asap
2003 Chevy Silverado Daily Driver, 408 Iron Block,
LS3 Heads/Intake, 231/239 114, 4L80e, Yank SST 3200.
Okay LTIT is disabled all together. I also disabled STFT OL. I have never touched the STIT cells so should I leave them alone or go ahead and double them?
2003 Chevy Silverado Daily Driver, 408 Iron Block,
LS3 Heads/Intake, 231/239 114, 4L80e, Yank SST 3200.
Okay so I did the Russ K config and made all the tuning changes. Still the same problem. I notices when I ran the Russ K config, my desired IAC position was pegged at 310 until around 120 degrees. Once that comes down, the truck doesn't drop idle when rolling in gear? Is this the problem?
2003 Chevy Silverado Daily Driver, 408 Iron Block,
LS3 Heads/Intake, 231/239 114, 4L80e, Yank SST 3200.
Did you do your RAF log or in gear or in P/N? Because you will need to do it in Gear as that is the 'worst case' for your setup as you don't have the luxury of RAF for both InGear and P/N. I think you will find that your STIT will be quite -ve when in P/N as a result, but that's the compromise.
Secondly, you don't have an IAC (Idle Air Control(ler)) if you are fly by wire so that makes no difference to you.
The STIT value I was referring to was the ST Adapt Airflow Max; it's up to you whether you change it, I was just suggesting as I suspect your STITs will be larger than those values and therefore if your remembered value is capped it *may* hinder the transition between P/N and Gear. You would have to log and see what your STITs are doing once you're finished. In the big scheme of things it won't have a huge impact.
Do you have an updated log?
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