'99 3.8L Missing/bucking Solved! (I think)

I think this problem generated more than 7 pages total of threads. To all of you that helped me, thanks. But in the end it looks like Divine Intervention has saved the day. Being out of work and low on money I could not afford to have my shop look at the problem so I turned to you nice folk and I prayed. I prayed hard.

I think I finally received Divine Inspiration to have a closer look at all the vacuum connections going to the back of the plenum. To my surprise I found that the brake boost vacuum hose was not secured to the manifold with the spring clamp. I found the clamp almost at the brake booster end so I moved it down to the manifold where it was intended. Another glaring issue was the larger diameter vacuum hose going to an HVAC control had no clamp on it and it was very loose on the manifold nipple. So there too I put a clamp to make it tight. It does not look like Ford intended this interface to have a clamp on it, but the hose was very loose fitting.

Results: After 4 days of driving it has not missed or bucked once. After driving in mountainous regions of VT with 6 people in the van it did not buck once. So after many hours of trying various things and buying a few new parts, I have to say thanks very much to all of you, but thanks also to God for hearing and apparently answering my prayer. I am just giving credit where I think credit is due.

Don't forget to give yourself credit for looking....and recognizing the problems when you found them.....as well as the ability to solve them.
It is GREAT to hear that you solved the issue......and I LOVE cheap and easy solutions....particularly when money is tight.
Also, thanks for reporting back with the solution, it will be helpful to others.

Glad that it worked.