I've read many threads on this. My 5.4 is ticking loudly at idle. It's from the passenger wheel well. It doesn't seem to speed up with rpm. Maybe tick goes away with throttle? I did recently change plugs. So maybe coil pack? Cam phaser? Exhaust manifold? How do I troubleshoot?

 

Ticking cam phasers are a fairly common issue on the 5.4l 3V. Though leaks at the exhaust manifolds can happen also which exhibits a ticking noise. A bad roller follower can also make the noise but is far less common. Try to pinpoint the noise.The below video has some information on the cam phasers, the noise they make when bad, where they are located and how to R&R them.

 

I'm pretty sure that's it! I'll have to verify with my stethoscope tomorrow. That explains exactly why it goes away under throttle. A cracked exhaust would speed up the ticking with the throttle. Mine goes away, but at idle- ticka ticka ticka.

 

This video explains some how the phasers operate.

 

hey kinda reminds me of when my exhaust manifold had rusted so bad it warped. Three of the stud heads were broken and I could feel the exhaust on my fingers. It was honestly the worst when accelerating from a dead stop, and not that bad on the highway.

Here is my thread on manifold replacement if thats the issue.
https://www.ford-trucks.com/forums/1...ticipated.html

 

Mine was a cracked passenger side exhaust manifold.

 

I did some more investigating today. I don't think it's the cam phasers, the valve cover fronts are quiet. I was wrong in my previous description, the ticking speeds up with the engine when rev'd.

With my stethoscope, the loudest ticking seems to be coming from the fuel rails!? Both sides too. The injectors, fuel rail, and to a lower level, the plastic intake manifold have the loudest of the tick.

I tried the coil packs and they are quiet.

So what would make the fuel rails tick loudly? A bad injector?

 

Perfectly functioning injectors click. As a matter of fact, my 3 valve 05 5.4 F150 had some noisy injectors. Sounded like little mini diesel in a drive thru. I didnt notice it until I put a fiberglass hood on with open ram air vents. I could really hear it.

 

Mine was the exhaust manifold on the passenger side. Replaced it and now sounds like new.