I got home today after being on the road all day and when I got out of the truck to open the garage door I heard a strange sound coming from my engine. It was a faint knocking sound, I thought it might be the cam phasers so I reved the motor up and the sound got faster as the motor sped up, but the sound didn't get any louder and it really sounded different than the cam phaser knock I 've heard in other truck.. After I got to around 1200rpm the sound stopped. I then let it sit at low idle for awhile and the noise didn't return so I sped the motor up to around 2000rpm then let it idle back down and the sound never came back. I could here the knock when standing next to the truck and it sounded like it was coming from the bottom of the engine, but it also could've just been resonating through the engine compartment and sounded like it was coming from underneath. I could also hear it through the wheel wellThe engine also ran smooth the whole time it made the noise. This is the first time I've ever heard the engine make this sound. Any idea what it might be?

Also, this is an '05 model 5.4 with 65k on the clock. The plugs were changed at 50k and the motor does have a slight cam phaser knock, but it's barely noticeable. Other than that the engine runs great.

 

You've got 65,000K weebie jeebies. Hang around, the sounds will get louder. Be patient, grinding and heavy knocking are damaging, some not so repairable as to want to have to deal with. Check your motor oil level. Be certain it wasn't foaming out. Ford has TSB for knocking sound in Catz out.

 

Timing chain tension noise is what I would suspect.
Lower oil pressure at low RPMs and the tensioners do not move enough.

 

is this something I need to get checked out ASAP or is it just a normal quirk of the 3v engines?

 

Unfortunately the solution involves the front cover removal.
Link to other threads;
https://www.ford-trucks.com/forums/1...-question.html

Ford Truck Enthusiasts Forums - Search Results

 

I was listening to some videos on you tube on 5.4's with loud cam phaser knocking and it kinda sounds like the noise my truck was making. My next question is: once the phaser knock gets loud will it always knock at hot idle or can it do it intermitantly? And, will the knock sound speed up with the rpm's of the motor until it hits the speed where the noise stops or does the knocking sound stay the same speed?

I drove my truck around yesterday and now I can't get it to make the sound. So I 'll guess I'll have to wait and see if it starts doing it more so my mechanic can hear it for himself.

 

Probably, finally the chain guides or tensioners will break and fill the pan with debris.