Ok I'll try to explain this as best as I can. I've got a 2000 f150 5.4 4×4, I've been hearing this humming or whining noise. At first I thought it was the power steering pump, but working on it today I realized its not. I took a screwdriver and went from spot to spot till I found it. On the passenger side on the top of the valve cover a few inches back from the oil filler neck is a pipe like tube that runs back along the engine and firewall. Now I wiggled that around a little and the noise changed. I hear the noise promptly when I shut the engine off for about a second or two. Please anybody, help. I hope I explained enough.

 

Change your PCV valve, - Motorcraft ONLY.

Just pull it right out while it's running, you won't hurt anything. That noise should stop.

 

Well I replaced the pcv this morning, seemed to work. Thanks, one less headache.

 

Np