No MAF on that one, it's speed density. Read BARO with a scanner and see if it's off for your altitude/weather condition. The two biggest factors used in calculating load are are MAP + TP.
that withstanding, you have two sensors that detect pedal pos redundantly in the pedal and two in the throttle body. if throttle body isn't following the request, engine will know and take appropriate action- reduced power mode.
On Silverados, I have commonly found both bad wire(s) and bad ground(s).
HTHY