RE: anti-knock sensor
These are notorious for knocking. Could be a few things, Most likly you have a blown plenum gasket. Its on the bottom of the intake manifold. Causes more knock and oil consumption. Easy way to check is to take off your ait cleaner, get a flashlight and a small mirror. Hold the throttle open (with the truck OFF) and look into the TB. Shine the flashlight down and if theres alot of oil on the bottom, the gaskets shot. Use the mirror to check in the corners.
Another thing that helps sometimes is to run a 180 degree thermostat. The cooler temp helps reducing the knock a little bit. Take a look at the plenum and tell us what ya see