I have a 2001 Chevrolet Silverado 1500 with the 5.3L motor not to long ago it started having a problem to where it won't accelerate past 20mph even if the pedal is to the floor I have replaced the following:
-Oxygen Sensors(all 4)
-Spark Plugs
-Coil Packs
-Throttle Position Sensor
-Fresh oil change and filter
What else could possibly be wrong to make it not accelerate! PLEASE HELP!!!!