stat-up/idle issues...imagine that?

[Superado]

start-up issues since new build install...
this is after ALOT of idle tuning...

LS1, Procharger P1SC, Patriot Stage III heads,
218/230 .605”/.604” 112LSA +3, longtubes

mornings...fires up on first turn over and usually catches itself and idles...
however, after several minutes of warming up @ idle, putting it in gear its fine but usually cuts off when I turn the wheel to exit the driveway...

rest of the day it MAY fire up on first turn over but will not catch itself and idle...
sometimes on the 3rd or 4th attempt it will catch if I don't decide to go ahead and pedal it...

if I pedal it for a little while, it idles fine...still wants to cut off when I start to leave the parking space though...this is after noticeably going into closed loop...

once I'm on the road...its all good...morning, noon or night...

tried adding more air at start-up...worked for a day or so...
tried adding a couple seconds to delay @ start-up...worked for a few starts, then right back to same issues after driving 15-20 minutes, parking and attempting to restart about 30 minutes later...

what specifically to I need to be looking at?
thanks in advance!

[Superado]

current tune...a work in progress...

[Superado]

made the following changes this afternoon...posted by SSpdDmon...so far...so good


Increased the Startup Friction Airflow Correction table for better starts. Although this doesn't really have to do with idle swing, I thought I'd include it because it seems to be a common problem. I increased this table by 4 grams/second across the board. Now, my warm start issues are gone. It was stumbling right after startup, barely running because there wasn't enough initial airflow. Adding air in here is a good, temporary way to add in the airflow, which will be decayed out after the first 30 seconds or so.
Changed the Learned Airflow Correction table by zeroing out the 0-20 absolute rpm cells. This means the car won't correct the learned airflow values (STITs/LTITs) until it's more than 20 rpms above/below desired idle speeds. With cam'd cars that have a choppier idle, the STIT/LTIT settings can be too aggressive. This softens them up a little.
Changed the Direct Airflow Correction table for High and Low RPM scenarios (Drive, A/C on, etc.). IMO, this was also making very aggressive airflow corrections. By zeroing out the 0-40rpm cells and reducing the remaining cells, I was able to prevent the idle from over-correcting and swinging up & down.

[Doc]

What year of vehicle? 512kb pcm or 1mb?

[Superado]

What year of vehicle? 512kb pcm or 1mb?

2000 Silverado

[Doc]

Are you using the stock 2000 OS or COS #3?

-Sorry I just downloaded your tune.

[Superado]

stock...
new tune:

[Doc]

Have you considered COS #3 with a 2bar Map sensor?

[Superado]

I do have a 2bar that I haven't installed yet...
new to this...not familiar w/ COS...