Rought idle

I am currently using ECU Edit to tune my 04 Subaru STi

I recently made a ton of upgrades and changes and finally got my car started up (the first time in over a year of upgrade projects.

My question is this:

The car takes forever to start; and I have to nurse the idle once I do get it to start or else it'll drop RPM to zero and shut off.

I know I need focus on smoothing out the idle but could someone provide just a tab more direction and focus on where to go next.

The only change to the ECU was to increase the injector flow scaling since I put in ID1050x (upgraded from stock)

For Context, I've upgraded the air intake, turbo inlet, turbo down pipe and exhaust. The car has the potential to "breathe" better now. Additionally, I've removed the TGVs (and I'm sure that is contributing to the rough idle) but I know I can smooth it out a bit and at least make it easier to start.

Any help is appreciated.

Thank You!

It sounds like it doesn't have enough fuel being injected. Are you able to take any logging of it cranking?

If you replaced the air intake with a bigger one, you'll need to take the adjust the MAF scaling. If you watched the Practical Reflashing course, you'll notice that changing the injectors and air inlet at the same time isn't a good idea as both have big impact on fueling and at this point you don't know where to do your correction. Injector Dynamics have well characterized injectors data on their website, so you might get away with it depending on the table you have access with ECU Edit, the one on ID website are based on COBB if I recall correctly.

If you still have your OEM inlet, you can put it back, adjust the tables about the fuel injectors (flow scaling, dead times, etc...), once it's good you can put back the aftermarket inlet and adjust the MAF scaling.