Thank you all I think I'll go the "hard way". Begin bench testing each of the (7?) sensors one at a time. Since that's the only thing not replaced. Just a pain finding the names of the sensors along with bech test specs for each

I was hoping for someone who knew of a TSB or common problem with 2001 Chevy Silverado 1500. Without that I'll just do it the long way.

 

Since I am not assuming anything, it is still a valid question.

Since I know know you are referring to a 2001 Silverado and there are no DTCs present, what engine is in your Silverado.