T4M2 initial start up

[Rockon]

Just got a rebuild on the road - using initial T4M2 high performance BIN with the minimum adjusted values as required.
Its a 5.0 HO from a '94 GT, GT40P heads, '93 Cobra Intake, 24lb inj, 76mm TB, and 80mm MAF.
I'm using TwEECer and I'm new to all of this but learning.

Cold start - revs high for ~30 seconds as its supposed to.
Settles down to the 850 rpms in the tune, but hunts for idle dropping to 300-400 before settling in.
Sound when it does this seems like a "sucking" type sound.

When warm - this seems to subside and reduce

Driving - this will occasionally happen when clutching close to and coming to a stop and will occasionally also stall out.
When clutching well before a stop and "coasting" in seems to not happen.

I am thinking its IAC but toughts?

I can post my BIN file if needed.
And no I haven't had a chance to data log and need to upgrade my equipment to try and do this.
I know its needed, but would like to try and trouble shoot past this issue and have it behaving even if not yet dialed in.

[decipha]

That's perfectly normal and supposed to do that until you dial in the throttle stop, fuel and idle air.

[Rockon]

ok thx