Stalling issues on return to idle

[corey1486]

Hey all

Engine in question;
LS2 SBE
Trickflow 215 heads
1.7 rocker arms
Fast 102
edelbrock 92mm DBC
stock ls2 injectors
long tube headers
BTR stage 2 LS1/2 cam
Lingenfelter 58x to 24x conversion.
P01 PCM


Engine was dyno tuned but still has lots of idle/drive ability issues. One has been really throwing me for a loop.

The car would die after a quick blip of the throttle, but I was able to get the throttle follower to slow the RPM drop so the vehicle does not stall. Now the issue i'm running in to is if i press the gas pedal and hold a steady RPM then let off the throttle it will die every time. I'm logging the throttle follower airflow and it doesn't seem to be adding enough or any airflow as the RPMs drop and the car dies. Can anyone offer some assistance?

I've attached a log of the issue. All the quick blips of the pedal the throttle follower slowed the rpm drop but any time i held the rpms up for a second and let go they just drop and if i dont press the pedal down the car will die.

Thanks in advance

[corey1486]

Anyone able to assist? I did play with the base running airflow tables today and now ive got the STIT improved. Still having the stalling issues on return to idle. Heres another log

[anniversaryss]

You have absolutely no throttle cracker as if its not even active.

Enable throttle cracker. Start out with a stock table and see if it helps.

Throttle cracker gives airflow to keep the rpms from dropping to quickly and overhsooting idle.

Post a tune

[ryan_axberg]

yea you should post up a tune. Just by looking at it I would make it to where you have more throttle follower at low tps input but you want to decay way quicker. That will add airflow when you need it and it will take it back out with in a couple seconds to where it can return to adaptive idle.

[corey1486]

Tune Attached

I thought the throttle cracker was only active when the vehicle was moving? In the logs the vehicle is not moving, we were just in the driveway. Adding to base running airflow helps with the issue but then it maxes out LTIT at -3.

[anniversaryss]

Tune Attached

I thought the throttle cracker was only active when the vehicle was moving? In the logs the vehicle is not moving, we were just in the driveway. Adding to base running airflow helps with the issue but then it maxes out LTIT at -3.

Throttle follower is active with change in throttle, throttle cracker (think of it as cracking open the IAC) keeps the IAC open to allow additional airflow to help the rpms from falling on their face but to come down on a "cushion of air".

Both have a decay rate that takes time to decay and both need to decay to 0 in order for idle trims to take over.

[anniversaryss]

My bad i didnt realize the car wasnt in motion. I took a brief look at the logs.