Low idle after pushing clutch in (driving)

[garrettcannon2525]

5.3 dbc gen 3 truck norris cam with a manual trans.

I've got the idle and everything else down pretty good, but when I'm driving and the light turns turns red, I push the clutch in and the idle goes waaaay down to like 200-300rpm and doesn't recover until you come to a stop. After you stop it goes right back to ~850rpm.
Timing tables are set correctly and is maintaining correct timing during the hiccup. Free revving does just fine, idle catches and everything.

I'm at a complete loss so any help would be appreciated.

[kyotey1693]

I'm at work right now and can't see your tune but I've fought with this pretty extensively with my 99 WS6 h/c/i car. Depending on which pcm and OS you've got, throttle cracker, throttle follower, and rolling idle (if you have it) would be the first few things I'd check. There are 2 switches on the clutch pedal. One is the start inhibit but the other is a clutch anticipate switch. If you'll log TC and TF you'll see they drop to 0 as soon as the clutch goes in until you get back to 0 mph when adaptive idle controls kick back in. There must be some other table that becomes active when the clutch in pushed in but I don't think hp gives us access to it. It's a real pain to tune. My solution was to bypass the clutch inhibit switch so I could always count on the TC and TF tables to work.

My latest tune is in post 29 of this thread. You're welcome to check it out. I'll try to look at yours tomorrow when I get back to my laptop.

Does it make a difference if the AC is on?

[kyotey1693]

I looked things over this morning, one thing that gave me a lot of trouble was the stall saver. It sounds good in theory but it always made things a lot worse. I'd disable that if I were you. You might want to try some of my numbers for TF, TC, and Adaptive Idle. I think it would help. But I also think that disabling the clutch anticipate switch is the key to getting those parameters dialed in.

You might also try some more underspeed spark. Most will tell you not to use more than about 4-8 degrees but it helps with mine, plus I like the sound. You can also try enabling spark smoothing. Seemed to help mine as well.

[Firebirdmuscle]

First, I would recommend dialing in your VE table getting that smoothed out first before chasing it much with cracker air. If rpm gets low on you while doing that give her some throttle to keep from stalling. That might potentially help a lot there. I don't understand all the WOT tries at this point when bottom end of VE isn't close, and when you do you are getting a boat load of knock, so much that's its maxing the max allowed table out. See how cleaning the ve up does and report back. With that being said, there are some things you can also clean up on the spark side of things that should help you out overall.

[Alvin]

I would not look at throttle cracker or follower tables at this point.

You fully warmed idle is way too high on IAC counts. You need to either open the blade position a bit or drill the hole in the blade a bit larger (my preference)

At the end of your log the IAC is open as far as it can open.. so its at its limit in how much air it can let in and it is still idling low with relatively high timing. This is a case of not letting enough air in.

Also there are several points I noticed it rich in decel, or rich at low RPM around idle. This will make nailing the idle down almost impossible.. Keep working on the VE table, get the IAC in range, and I'll be the issue will resolve itself.