Working on my idle tune

[blsnelling]

Could you please post a screen shot of your Idle -> Learning -> Parameters?

[WeathermanShawn]

Glad to hear RPM/Idle Speeds are on.

Sometimes Spark will drop..Rpm's will fall and then hopefully the Spark/Airflow changes we made will kick in and prevent the stall.

If you want to fine-tune some of that, then look over B5934, B5935, & B5936. Those limit the Spark swings you get at Idle.

I have not used Stall Saver, but would be interested in knowing how it works. If you find your vehicle is more prone to stalling at higher ECT's, you can add a little more air into the RAFIG, RAFPN at the appropriate ECT.

[blsnelling]

I'm still having occassional issues with my idle. 99% of the time, it's perfect. Where I'm having issues is if I'm doing stop-and-go in a car line, such as a drive thru. I'll be setting there idling, just barely touch the throttle, I'm talking like 1000-1200 RPMs, move forward a few feet, let off the throttle, and it'll dip way down to like 300, try to catch itself, and then die. If I do even a couple MPH, it won't do this. I've increased the throttle follower delay, and decrease the decay rate. But it's like this isn't being activated when I give it that little throttle and/or move that little or slowly. When I move forward a little faster or farther, I can see the TF delay and it's decay, and the idle settles down slowly. Where's the throttle plate supposed to be? I have an adjustable stop on my t-body. I've tried opening it up, but with only 1/4 turn more, the idle starts surging up and down, non-stop. I'm guessing that I'd need less desired airflow if I left it there? Maybe adjusting the stop isn't part of the answer. I'm not sure what else to try.

[WeathermanShawn]

Its a tough call on what is happening.

Two other things to think about..Is your Spark values changing (dropping rapidly) when this happens. Secondly, if your fueling goes momentarily rich or lean..one would bog and stall, the other would also stall.

It someone still sounds like not enough air, followed by a slightly unstable Spark when you are going to the High-Octane Spark. A log right at the stall point might give a clue..

[blsnelling]

I'm sure I can duplicate it and catch it in a log file.

[WeathermanShawn]

Yes, that would be a good idea.

Its right in that transition where both TC and TF may be active. Also, if I recall we may have '0' air in the lowest TF TPS % settings (B4315). That was to prevent Throttle from hanging, but that may be where you are having problems.

I am not sure if the manual throttle adjustments are helping or hurting...

[blsnelling]

I've changed B4315 several times. I'm not sure where it is right now. The laptop's in the truck. Which should activate TC and TF the earliest?

[blsnelling]

Here's a log of it happening. I captured both low dips to maybe 300 where it caught it and recovered, and also where it died. You'll see other times where it doesn't dip at all. BTW, max speed and throttle for idle are both set at 1.

Idle_03.efi

[WeathermanShawn]

If I look at Frame 34 just before it died, I see both the TC and TF go to zero. I take it your technique is the car is in gear, then you put it into P/N (forgive me, it has been a while since I have driven an Auto)?

It is only stalling in P/N or when you go from in Gear to P/N?

What I would do is look at an exact Frame # on you log, then go to the data page. Preferably using g/s, at the exact stall frame..list exactly the Value of each Airflow. I guarantee you it will only stall when there is not enough Airflow for that particular IAC position.

So, perhaps we are back to P/N Airflow. Regardless of what RAFPN says, you may need more air at that point.

At of curiosity what is the Airflow Value of 400 RPM on Table B4309? I have mine at 4 g/s. I see you go to '0' TC when you stall. That may be normal as the TC deactivates, but I am just curious.

[blsnelling]

I does not try to die when put in gear. What I'm doing is holding the brake and giving it 1000-1200 RPMs, then letting off. That's when it will do it's thing.

B4309 is 4.00 all the way across at 400 RPMs. At 1000, it's 0.00-.71. That might be it right there. Once I increas the RPMs above 1000, I'm getting way less air on the way back down. Maybe I'll make the 1000 row 4.00 as well.