start up airflow decay?

[achidotcom]

how can i adjust start up airflow decay?

i have problems with idle, and some ocasional backfires.
on a cammed 98 suburban k1500 5.7 vortec.

[SSpdDmon]

That table is for start up only and decays the additional airflow provided during start up over a matter of about the first 10~15 seconds the engine is running. If you're having idle problems, have you adjusted your fueling, timing and your Desired Airflow table? Those should be done first. Then, you should tackle start up issues. Otherwise, you'll be tackling them more than once.

[achidotcom]

i have tried initial fuel prime with minimal results but it did help to lean the prime. also played with timing tables and fine tune timing. and airflow was adjusted as well
my idle goes like this

at first start up of the day, it will start with just turning the key, idle will be at about 600 rpm for 8-10 seconds then jump to 1300 rpms for about 4 seconds then idle at about 675 rpm.

if i kill the engine then or even after normal op temps, it will not start without me stepping on the accelleratorpedal for about 5 seconds then it will idle on its own.

then anytime it is started its not bad,
occasional backfires when i get on it hard it will pop once and go.

when i am on the throttle and let off the idle will lower to about 500- 575rpm and slowly climb back to 675rpm.

furthermore at stops it will somtimes surge at idle from 575-675rpm.

[SSpdDmon]

Hmmm....can you post a stock tune and your current tune?

[achidotcom]

stock and current

3250

3251

[SSpdDmon]

I took a look and it seems you are missing quite a few tables. You may want to look into/research upgrading your PCM setup to run a new OS. With a more recent OS will come many more calibrations to help with idle issues.

[achidotcom]

i have looked at the 0411 swap but didnt think i needed it.
maybe i do now. its a cheap swap but labor intensive.

thanks for the help