Check Engine Light Code P1103

[Wizard]

P1103 is the wastegate actuator. THat is probably becuase you unplugged the boost control solenoid when you installed the MBC. Plug your BCS and clear the code.

Your fuel cut can be many things. But i've rarely had fuel cut with even a modified BCS. I would check your UICP for tears at the couplings and proper install. Also, check the BOV for leakage, maybe tighten the spring in it. Since you started having your issues with the UICP and BOV install....that is where you should look for your problem.

Wiz