5.3L valvetrain tapping like a sewing machine.
140k multiple engine valve tap. Rebuilt
cylinder heads with new springs.
Replaced pushrods, all lifters. Everything
looked and measured like new. Multiple
engine misses with traction control
codes. I have adjusted valves by the
manual. Oil pressure by professional
gauge within normal specs. Drives good
down on power. Feels like a problem
with did system? What could be
happening?