The TPS is integrated into the throttle body on Crossfires.
You can remove the black plastic cover and spray some electronics contact cleaner on the wiper fingers and the board while manually moving the butterfly back and forth.
You may have any number of problems :
gas pedal assembly
throttle body
fuel pump
fuel filter
fuel relay in the RCM module
intermittent electrical connection somewhere
You can monitor the fuel pressure at the test point on the injector rail, 55-60 PSI.