Originally Posted by moosestang
Use quality oil, quality oil filters and change it often. The variable cam timing uses small screen in the solenoids that can get clogged and cause oil pressure loss to the cam phasers. Then you get the noise. Sometimes the solenoids themselves will fail, but it's not that common.
I just did the solenoid test, to give you an update, I swapped them and the noise is still on the same bank. And anyways they were clean, no clogs. Unfortunately.
if they were causing the issue it was better, easier and cheaper to replace but I think the sprocket is gone
(thx for the actuator tip btw