I have a 2002 5.4l Supercrew with 81k. Here is the issue, I am getting a loud knock or you could call it a clank on the passenger side of the engine. It changes with the RPM and seems louder at the top of the engine vs. the bottom. I checked all the ex. manifold bolts and all 8 seem to be intact.
Please help as this is my DD!!!!!

 

I've heard PCV valves do that. The last one I heard was in an 01. Sounded like a rod knock lol. It was a Fram PCV valve.

Third party PCV valves don't work that well because their to restrictive. The correct Motorcraft valves have twice the margin space.

That's what it sounds like to me. A Fram valve will cause the engine to use oil as-well.

So check that out, yea, -they do get real noisy..

 

Also check your spark plugs. You may have one or more loosening and getting ready to eject. Retorque them to 28 ft/lb.

 

Run the engine with the serp belt off to make sure it's not external.

 

OK checked the plugs on that side and they all felt tight,(man that last one is a PAIN). I pulled the PCV out while running and still get the noise.
It sounds like it is under the valve cover, what are the chances of a broken valve spring or bad cam bearing?? I would say it is a bent or broken valve but the truck runs great just sounds like it has a big rock in the head.

 

Check your oil level.
In my case it was really hard to tell where the noise was actually coming from without a hose or a stethoscope to zero in on the noise. If its coming from under your valve covers your in the same boat as me.Your hydraulic lash adjusters (lifters) might be tapping. mine did when the oil ran low and i ignored it and now I am in automotive hell. Pray that adding oil helps or your in the same boat as me

 

A thought:

https://www.f150online.com/forums/v8...4l-triton.html

Long thread, but read it all.

 

You know JBrew, my motocraft pcv valve makes a high pitched buzzing noise. this right? its quite loud. I did replace it with a third party valve and it was worse, lol.

 

I never heard of a Motorcraft valve making noises like that, but a bad one could. They can get bad real quick in cold climate conditions when you constantly use the vehicle for short trips. That tends to gunk them up.

 

It almost sounds as though there is something under the valve cover taping on the cover from the underside. If you rev it, it will get louder, but if you are just moving along normally the volume doesnt change much. The sound does change with the RPM, I looked in the oil fill spout and at the end of the cam I could see some threads??

 

Did you read the thread I linked to?

 

He doesn't have cam phasers, does he?

 

Your describing the sound/problem I have. Do this, look up on youtube "lash adjusters". There are a couple of different videos of different cars that make all the same noise, but try adding oil or changing your oil to see if it helps the noise.

 

Yep!
I am hoping that it is something that simple!!!

 

If you can get the valve covers off, you should see that right away if that's what happened.