Boost drops to 0 at 4500rpm

[Xero_Tolerance]

THe title pretty much says it all. I just installed my walbro 255 fuel pump and was testing it out. It ran pretty nicely for a couple or days, but recently anytime I get on it and it's at full boost over 4500 rpm it drops straigh to 0 and hardly accelerates at all. If I ease past 4500 it can hold some boost, not full boost, but it doesn't drop straight to 0. I logged it and the fuel trims are all right about at 100 cause I got my s-afc setup right, but something is still messed up, obviously. Anyone have any thoughts on the matter?

 

[Xero_Tolerance]

No one has any clue why that would happen? I mean could it be a boost leak? I just want to know where to start looking.

 

[leet]

It would be helpful, to have a clearer picture of what you have modified on your car.

 

[2.4 turbo Hyped]

Could be a clogged catalytic converter. Could be a pre turbo exhaust leak. Cant think of much else right now.