P0171 and P0090 help please

[MP3DG]

I have both of those codes, I've searches the forums for possible solutions I've checked for vac leaks and I've replaced the fpr solenoid still to no a avail I have both codes. I'm getting a fuel cut around 4.5k I've recently put an ATP wastegate that spikes to 8psi would I be getting these codes due to the higher boost without a tune of any kind? It likes to come on and off as well it went off Saturday morning and came back this morning! Kinda stumped! Any help would be greatly appreciated

 

[protege3690]

thats a system too lean code. you may have a vacuum leak around your IC piping. or a vac line thats not on properly. recheck all your plumbing first.

 

[dirtysouth_msp]

For p0090, check your fuel pressure regulator control solenoid for proper operation. If it is not working properly, it could cause both codes.

 

[MP3DG]

If my understanding correct if I follow the vac line from the pressure regulator to the solenoid it's the one by itself kinda by the throttle body correct? If so I did replace it ready. I'm wondering if its the fuel pressure regulator itself.