2001 Porsche 996 turbo, running GT660 EVOMS tune with 1050x injectors, K16 billet turbos, Hitachi Mass Air, Catless Exhaust, intake tubes off Turbos.

Car has been pulling codes P2135 and P0121, thought it was Pedal Potentiometer, so had it replaced. Drove home and it still comes back. Not that this is related, but I am also getting codes P0051 and P0151 as well regarding o2 sensor area. Pedal will go into limp mode and open 30 pct on wide open throttle.
I read somewhere online, that the brake switch can go bad and cause these codes. Anyone heard of this? Please advise.

Thanks,

Steve