Have a 2023 F150 Kr with 3.5 with 50k miles.
upon cold start I have a noise/rattle that is intermittent. It’s not right at start up. But at every segment when rpm’s reduce.
The first is right about 40 seconds there are 4 of these noises back to back,

The next is one of these noises at 1 min 21 second

And the last short segments of noises that continue for awhile start after last rpm reduction about 2:14

truck is currently at dealer and they are saying cam phasers. However it’s a period after start and not like the cam phasers rattle that happens right away and then goes away

after I had dropped the truck off, I noticed this part is moving when the noise occurs. I did not notice it at first

will try to upload videos but have to chop them up to load

Circled part is you can see movement at noise in video

 

Video at first phase cold start, what would be 41 seconds. But had to chop video length to upload

 

Second phase of rpm reduction at would be one minute twenty seconds from start. A single noise/rattle

 

I think my 2023 f150 has same noise.

 

Google 3.5 Cam phaser and its a very different noise. Could be wrong but I suspect if those were cold starts it's an injector noise adjusting as the temperature starts to rise.

 

Thanks for the video, after checking my 2021 F150 3.5EB engine comparment, I believe that moving part is some kind of control arm to a valve or solenoid on the exhaust, and I think this noise has nothing to do with Cam phaser, and it seems normal control noise to me. Like my F150, every time when I open my driver door, I can hear a lowed motor noise from engine compartment, not sure what it is doing...