Im workin on a 99 4x4 with a 5.2... Its kickin out code po201 po203 and po206... All are injector codes.... The injectors are fine and spray a nice pattern.. They are gettin a good solid signal but the truck runs horrible... Any ideas????

 

It sounds like the plenum gasket. With the truck off,Take off your air cleaner, open the throttle body and shine a flashlight in the manifold. If its full of oil your gasket is bad.