Warm startup issue

[the_merv]

I've been chasing this issue for a long time, everything else seems to be fine. After driving the car and parking it for 10 min or so, you start it up and go to drive, the car seems to low idle and want to die for about 5 seconds, then it comes back to normal with no issues. I had a chance to log it, it seems the IAC goes to zero steps when it does this issue, and then comes back to normal. Only does it when the car is warmed up. Attached are the tune file and the datalog file, feel free to take a look. When I bought this PCM someone already had tuned it so they may have tweaked something I can't find.

Setup is a stock 5.3l, LS6 Intake, GM Hotcam, T56 6spd.

Thanks for the help.

Files:
SS 5.3l T56.hpt

SS STALL ISSUE.hpl.

[GHuggins]

Go to the tune repository and download a stock tune file of your year model and build to compare to. Just from a glance it looks like quite a few of your airflow tables have been messed with especially under the throttle follower section. Also highly recommend adding stit and ltit to your datalogged pids. Bet your going to find them pretty far off. If your ltit is off, it will save the incorrect "adaptive setting" in the ecm even after changing the tune. This Will cause you to chase your tail for ever... You can disable the ltit in the tune by zeroing out all of the adaptive idle airflow section then tune in your braf correctly using the stit as your guide. You'll also have to unplug your iac and tps then cycle the key to reset your iac if and when you make any changes to the iac steps in the tune...

Know it's not much, but hopefully will help you get started

[blownbluez06]

I've been chasing this issue for a long time, everything else seems to be fine. After driving the car and parking it for 10 min or so, you start it up and go to drive, the car seems to low idle and want to die for about 5 seconds, then it comes back to normal with no issues. I had a chance to log it, it seems the IAC goes to zero steps when it does this issue, and then comes back to normal. Only does it when the car is warmed up. Attached are the tune file and the datalog file, feel free to take a look. When I bought this PCM someone already had tuned it so they may have tweaked something I can't find.

Setup is a stock 5.3l, LS6 Intake, GM Hotcam, T56 6spd.

Thanks for the help.

Files:
SS 5.3l T56.hpt

SS STALL ISSUE.hpl.

Try this

[the_merv]

Thanks guys I'll have to check it out. I had it out yesterday, got the timing at idle to hang around 15*, matched the PID tables to the stock 2002, I'll have to check into the other stuff you all mentioned. I'll check out that file above and see the changes.

[the_merv]

Fixed...wont let me delete the post so I'll fill it in..

Increased base running airflow about 40% over dynamic flow at the idle rpm I have it at. After doing that and touching the throttle cracker & follower tables up it drastically improved. No stalling, drives perfect. Getting better the more I drive it so maybe it's learning itself.