So I have a purely SD tune (no MAF) on my LS2 that's been running fine for a couple months now. But the problem is that after I flash the computer with some adjustments, I have a hard time getting the car to start and idle.

For example, after changes are installed (mind you these are minor changes not a completely new tune) I go to start the car and the RPMs jump up widly from 1000 to 3000 a couple times, then they just drop and the engine stalls. Unless I press down the pedal hard and give it a big rev, the engine will keep doing this. But after I give it a big gulp of air it idles just fine and subsequent startups are fine.

What would be causing this? Could the startup airflow table be messed up (even tho startups after this are fine, just the first startup after the flash is the problem)?

 

Cranking VE and afterstart enrichment, your idle
airflow target and the quality of the lowest cells
in the primary VE table are where it's at. 400RPM
is hard to hit for real tuning, you have to make a
good guesstimate (guess lean, if in doubt). The
curves ought to look at least like they're following
the trend from more sensible regions.

Flashing means unlearning all the idle airflow trims.
I like to set idle air targets high, and let the RPM
trim bring them down over time.

 

It has nothing to do with the tuning and more to do with running no MAF.

I am accustomed to this after tuning a handful of turbo car/trucks SD OL. The first start or two can be gross after the flash even with maf fail at 0. Then its all good from there out, well that is if the tune is good. It seems they take a while to fail the maf even when the fail is at 0.

I have never tried to address it as I could really care less if it starts good the second time and every time from there on out.

 

Yeah, it's fine after the first startup...

So I should just bump up the cranking VE and afterstart enrichment (by how much do you think) and let the computer learn those overtime to normal.