My 2004 linc ls (6cylinder) is not going into overdrive. what could this be?

SOURCE: Linc LS v8 05 will not excellerate only idle,scan code #p2104, p2111, what's going on.

code p 2104 refers to throttle actuator control(TAC) system--forced idle mode===causes ---wiring--TAC motor--ALL sensor--ECM
codes p 2111 refers to throttle actuator control (TAC) system--actuator stuck open====causes --throttle body--throttle valve tight tight/ sticking
also refers to TAC system --circuit malfunction=== causes wiring short to positive ---short to ground ---TP sensor ---ECM
also refers to brake vacuum---implausible signal====causes ---wiring--- vacuum sensor--- mechanical fault