Re: 80k Service? and Throttle Position Sensor?
These trucks have timing chains (no belt) that last the life of the motor, they don't need valve adjustments, etc. So... they only really need fluid changes, spark plugs, and serptentine belts throughout the life of the motor.
If you regularly change your oil and change your plugs/other fluids every 50k then no... you don't have to do anything special unless something breaks. Before you replace the TBS I'd de-carb the throttlebody and re-set the codes.
2004 GMC Canyon - DD/toy hauler
2001 Quicksilver Z06 - NASA TTA racecar
2003 Torch Red/Tan Corvette Convertible