I have a 98 Ford F150 TritonV8. I use a very nice mobile mechanic who I asked to change my plugs due to bad idling & stalls.
I wrote down exactly what he told me to buy that should fix it. Here goes:
PCV HARNESS ON REAR OF INTAKE MANIFOLD.
When I went to my local parts house the man acted like I was speaking Martian. Does anyone have a better part description?

 

He probably meant the rubber elbow on the back of the intake that connects the PCV tube to the intake, it rots out and causes a vacuum leak. Do you have a 4.6 or 5.4? You may be able to buy just the elbow, or you may have to buy the whole tube. Go to the Ford dealer, this isn't something that a parts store would have. However, if it's a 5.4, I think Dorman 46017 is the elbow. Otherwise the assembly is dealer-only.

 

I think even a blind hog finds corn every now and then. Would this be it? Tried O'Reilly's, Auto Zone and finally Advanced Auto Parts. Very knowledgeable parts counter man.

 

I *think* that's the one for a 5.4. Show it to your mechanic and ask if that's what it needs.

 

Will do. Thank you so much for your help. I'll let y'all know.