Was getting P0017 every now and then on my 2005 Chevy Colorado 3.5l with 113k and now it comes on regularly after being cleared. Changed the valve solenoid of course and the code came back. Had this same code a year ago and changing the solenoid fixed it. Seems the problem has worsened. Does changing the cam sensors or o2 generally fix this problem, or is that rare? After some research is seems I might be going down the road of a timing change job or maybe just flushing the engine with sea foam? Engine runs fine and performance doesn’t seem to be affected. Any ideas?