Startup idle surge MAP sensor?

[5ft24]

this is an odd one, so bear with me.
2006 GTO, LS, Manual Trans.. BTR PDS stage 3 torque cam, LSA running 8.5PSI, FIC 1000 shorty injectors, Kooks 1 7/8 Long Tube headers with high flow catted mids and magnaflow 3" competition cat back system, BoostDistrict cold air intake with LS7 MAF, DW300C in tank pump, UPP Aux fuel system with external 340 LPH pump triggered at 5PSI, DSX tuning Flex fuel kit.
Tuned July 2019, made 610HP on E85, 576 on 92 octane. Driveability is great, MPG is even decent.
Car lives overnight in the garage (semi-heated) so it's never under about 55-60 degrees even when it's in the 30's outside. startup, even on E85 has been normal. over the last 2-3 weeks, I've started getting a bad surge on cold start, or even if it only sits a couple hours before starting it back up. When it starts, I can blip the throttle and the surge subsides. Checked all vacuum lines etc for leaks, checked all plumbing between the MAF and TB for leaks as well. Nothing. Threw Torque Pro on it since I didn't have my laptop when I went to leave work one day. MAP read good KOEO. fired it up, driving out of the parking lot and when I decel, my Vacuum/boost guage on the dash goes to about 22" vacuum, but the MAP was only showing about 16". did it a few more times to verify. (boost guage has it's own MAP sensor). took off and pulled it to about 5PSI boost and boost read ok on Torque, and after hitting positive pressure, on decel, the MAP would match the Vacuum/boost guage again at 22in vac. Could the MAP sensor possibly be the source of the surge?
attached is the Tune and Log of the cold start when I finally brought the laptop down yesterday.
Thanks

[geneass]

Maybe timing related, check all temp related stuff. Mine was doing the same, very little input on go fast pedal and it would straighten up. That's at cold start idle. Lakegoat suggested to add to minimum air flow and I did but haven't checked on a first time startup after sitting overnight. The first thing I did was remove startup fuel and take some fuel out of the ivt gains table at the temps I was having issue at. It seems it helped, but like I said have not tried on cold first start of the day yet

[Lakegoat]

Looks like it is too rich at idle. I see that you did the double stoich, but I don't understand the stoich numbers. Since you have a 2.5 bar map, you should go ahead and do the 2 bar upgrade.

[5ft24]

Not sure why my tuner did it the way he did. There are some oddities in The tune as well in other areas. It has ran great for over a year, and just now this issue started. Waiting to hear back from.my tuner. Hopefully tomorrow when he get in to his shop.
I had asked why he didn't do the 2 bar OS. He doesn't like speed density tunes for the street. MAF is more forgiving if things change...

[blindsquirrel]

MAF/blended still works just like stock with the 2-bar OS. I don't know why they put that 'SD ONLY!' scare-warning on it, it's not true.

[5ft24]

if I update to the 2 BAR OS, does it wipe the tables and I have to start from scratch, or does it keep the tables as they are?
Also, does it cost any additional credits?

[blindsquirrel]

No credits. The only things that require changing from the stock file is, it defaults the MAP linear/offset to 200/10.33 (just change it back to whatever matches your sensor), the boost VE & boost enrichment tables are blank to start with, and the fan vs. ECT axis is lowered so the cell values have to be offset to the right if you want to keep the same setpoints.

You can apply the OS to your current file, save as new name, and study it without having to write it to the car, you know.

[5ft24]

Ah Cool.
Thanks

[5ft24]

MAP wasn't the issue, found some info in other posts so added a touch more airflow in the idle final base airflow table. Starts up and purrs like a kitten. no more surge!