Thanks for the input guys!

 

I am assuming no codes or CEL yet? I went down the same path as you. Same flash ran great in the beginning then issues. Found a split hose and it ran fine for a few days, now back at the shop with new/more codes pertaining to O2 sensors, though I don't think that is the problem. Working with Tony and my local shop to pinpoint the issue. Guesses at this point are plugs/coils or MAF.

 

You can disconnect the MAF and run the car. You will get PSM/ABS code and check engine light, but no big deal. If the car doesn't stutter during a run with the MAF disconnected, I would say that is your issue. I just went through this. Put a new Bosch MAF on and reset the codes. Running great so far. Good luck.