So this has been happening for a while now and I'm kind of at a loss with it basically what my car will do is with very little throttle input my car goes pig rich for like 2 seconds then back to normal.
So say if I'm in stop and go traffic let off the clutch give a little gas then have to push the clutch back In to stop my car will shoot to 10.0afr for like 2 seconds kind of bog then go back to 14.7 to 15.1ish

Mods on the car are
DW200 fuel pump
Upper lower icp
Injen CAI
evo 9 diverter valve
Stock fuel injectors

The car cruises Great at 15.1ish
My turbo spools at 12.1 and tapers to 11.2 by redline
The thing I think it's doing is bouncing into open loop with the slight movement but I'm not 100% sure on this my fuel trims are within 3% so I'm pretty sure that's not the problem...

My next thing to try was forced the car in open loop 100% of the time and retune the map that way and see if it still does it but that's a lot of work.

PS i also threw a new front O2 sensor on to make sure it wasn't bugging out

 

Fuel pressure.

 

I have not checked my fuel pressure it's just the stock regulator what would cause it ? Bad regulator to much fuel pressure is it because I swapped my new pump in the old one died I did have to dial my fuel maps back in but the car drives completely normal other then the 1 issue...

BTW it was on the old stock pump and now that I think of it started happening after my pump install but I was told the stock system could handle a DW200 just fine since it's the same flow as a walbro255 hmm I have no way of checking pressure

 

Hmm no other input ???
When you install a fuel pump is there anything other then the tune that needs to be taken care of ?

 

There's no software tuning to do with just a pump.
Make sure the pressure doesn't change and when it does, fix the pressure problem.

That's why pressure gauges exist.

 

Well I know that but what I'm asking is why would my fuel pressure rise up i see many people running walbro255 on the stock system without the stock fuel pressure regulator and rail with no issues in running a dw200 pretty much the exact same flow chart as a walbro255 maybe a little higher...

If it is my fuel pressure what should I go with an after market regulator that is adjustable I was looking at the fuel lab fpr and it seems pretty nice I don't want an aeromotive one it's what I had on my STI and it always had problems...
I'm open to suggestions thanks