Cold start up no idle and then at 1:50 the IAC opens:

[1CAMWNDR]

OK This is a first for me. On the last few colder mornings my car will not idle unless I keep the throttle at 3%. Then at 1:50 it wakes up and idles fine.
Here is what I saw on the scan:
The IAC desired g/sec is at 0 untill 1:50.136 and then snaps to 32
The IAC desired position is 0 untill 1:50.354 and then snaps to 170
The IAC position is 0 untill 1:50.136 and then goes to 3, at 1:50.354 goes to 41, and at 1:50.541 goes to 80.

What do I adjust to fix this? The IAC reset position is 270 so I thought it would start there as soon as I turn the ignition but I guess not. Frost did the initial tune and has helped me a ton polishing it. I don't want to take any more of his time for a 1:50 issue.

Here are the log and tune.

[1CAMWNDR]

Bump for a completely lost novice tuner.

[Sam88gta1]

You are commanding to much Base running idle airflow. Until its below 40.0 g/sec it will not open the IAC.

[Alvin]

You can try to open up the idle airflow limits. They are right underneath the IAC vs Eff area under idle -> Airflow.

Another thing to remember is STIT and LTIT's are disabled and will not update above a certain throttle position (very close to 0%). So up till 1.50 you where holding the idle open with your foot and the STIT's and LTIT's where not active trying to catch and learn the idle.

[1CAMWNDR]

Thanks for the infoYes, it will not run at all if I don't hold the throttle a little. Then the IAC pops open and it runs well.

[1CAMWNDR]

Changed the too high Base RAF to 39 g/sec and still got the same result .

[WS6FirebirdTA00]

Lower your idle airflow in the base airflow table. At 20ºC make it around 20 g/sec and then go up from there in 3 g/sec increments as you go down in ECT. Looks like you are outside a high limit in the idle airflow table and once it comes to 32 g/sec it goes active (idle desired airflow is commanding 0 on startup). This may be a bug in the OS unless I am missing something else.

Depending on your TB and where your IAC is at idle, you may need to crack the throttle open or drill the blade to get the IAC counts down at idle, then recalibrate your effective area table to allow for accurate IAC step predictions. I would also recommend you fix the RPM table as well, you need more RPM when cold if you want the car to run well. Also, since you are running SD, you need to setup the OLFA table better to compensate for fueling when cold. Dial the fueling in hot, then make corrections here when cold. This will also help cold start once you fix the airflow issue.

[1CAMWNDR]

Lower your idle airflow in the base airflow table. At 20ºC make it around 20 g/sec and then go up from there in 3 g/sec increments as you go down in ECT. Looks like you are outside a high limit in the idle airflow table and once it comes to 32 g/sec it goes active (idle desired airflow is commanding 0 on startup). This may be a bug in the OS unless I am missing something else.

OK. Did that. We will see if that is the problem. Thanks for the heads up!

Depending on your TB and where your IAC is at idle, you may need to crack the throttle open or drill the blade to get the IAC counts down at idle, then recalibrate your effective area table to allow for accurate IAC step predictions. I would also recommend you fix the RPM table as well, you need more RPM when cold if you want the car to run well.

It is a 4BBl throttle body so cracking the throttle blade is just like on a carb. We will see if that is needed, but once the IAC pops open it idles great. This only happens on colder mornings. The rest of the day it idles gerat. Target idle speeds bumped up.

Also, since you are running SD, you need to setup the OLFA table better to compensate for fueling when cold. Dial the fueling in hot, then make corrections here when cold. This will also help cold start once you fix the airflow issue.

I assume this means richer when colder??
Thanks again for the wisdom!

[WS6FirebirdTA00]

Yes, you will have to make it richer when it is colder (if you command too low the car may run really rough or not run at all).

[1CAMWNDR]

It worked!!!!
I don't know which tweak did it, but it no longer needs a foot on the throttle to idle on a cold morning. Now I can fiddle with warm idle AFR and cruise AFR, and try to polish out a minor bucking at light throttle below 2500 rpm.
Thanks WS6FirebirdTA00 for the help.

[WS6FirebirdTA00]

No problem, glad it's running