[MT-2500]

2004 F-150 4W 5.3 engine AT 157K miles.

Code engine P0012.
Has had cam sensor codes before and both cam sensors replaced.
Now Code P0012 and engine at start up rattle and after warm rattle on both front camshafts sprocket area.
And under 1200RPM and engine miss.

Replaced no 2 VTC sensor pass side.
No change.
VTC sensors readings go way high one bank and low other bank.

Under TSB 06-19-8 10/02/06

They refer to replacing VCT camshaft sprocket Phaser kit.

Is there a good way to diagnosis it to see for sure what it needs?

Thanks for any help.
MT-2500