What's This Noise?
 

Hey guys!
Back again, I just bought an '07 F150 5.4 XLT S'Crew, It's an amazing truck. It drives well and is very clean. However, it's makes some odd noises, can anyone identify this one?

It's doesn't really sound exhaust related to me, more like a knock...

http://www.youtube.com/watch?v=v_Q3gjFyUZA

Stats on truck if you need them:

2007 F150

• XLT
• 4x4
• 5.4
• 3.73 gears
• 69k Miles

With a little research... Cam Phasers.

Mine sounded like that...had the cam phasers swapped out...went away for about a week then came back. Still does it today

Yeah, Doesn't sound like I'll be getting it fixed. I've read about too many cases where it's returned after the $1500 repair bill.

Will it do it sitting still , foot on brake in drive rpms held between 800 to 1200? If so , it sounds like the phasers. Mine does it , it is very annoying.

mine does it in park, raise the rpms up and starts getting worse then stops right after 1200rpms

Yes , i also just tried it in park. clattering and tapping away , this engine sounds terrible !