I now notice a fast ticking noise right after start up, that fades away and stops. Never had this before, did they install phasers wrong?

 

That's what the cam phaser replacement was supposed to fix, if yours was not rattly why did you change them out?

 

It's not the phaser noise which sound is very loud and Diesel like. I'm talking about what sounds like fuel injectors. It may have been there all along and normal, but I've never heard it. It follows the fast idle and gets very quiet after the fast idle stops, so it probably is the fuel injectors.

 

If you are hearing that after cold start up and it quiets down after rpm drops it's likely wastegate rattle, common and annoying, but not a problem.

 

Nope heard quite a few waste gate rattle videos and that is an inconsistent ticking with a metalic clang. Nothing like the quick consistent ticking I hear. As I said, I think it's the fuel injectors.

 

I've noticed this too. At about 30 sec in for the first idle speed drop.

I think the DI turns off at idle after cold start up... Need to look up the report I was reading about this to see if I was remembering correctly. Maybe we are hearing the DI injectors stopping?

 

See this report, very interesting. Page 39 shows how the DI and PFI operates at cold start.
At startup, both are operating at 70/30 ratio DI/PFI. After 60 sec the DI turns off and uses PFI only.

I think this is the distinct change I hear on my truck...?

Can you time it and see if it is consistent or corresponds with this?
​​​​​https://www.nhtsa.gov/sites/nhtsa.do...nts/812520.pdf