P0016 - rebuilt engine.

P0016 is a timing DTC code.

The VVTi actuator is an aftermarket from Autozone, could this be at fault?

Engine ran fine for 30 straight minutes, so not sure what the issue could be. I'd imagine if timing was off (I checked it for 100 revolutions before sealing it up, so I doubt it) it would have coded right away.

 

Took the actuator out, tested it with a power supply. Works good.
Checked the little filter for it, no issue.

Put it all back together and the code has not come back. I'd think a mechanical timing failure would trigger it much faster.
According to the workup, the time to trigger is only 60 seconds.