00 740iL - Running sluggush, a little help?

2000 BMW 740il, 205k on it.

Seems the problem started at speeds of like 35 to 40, just kinda had a skip or miss, studder something like that.

Put some Sea Foam in it and some new premium fuel and have ran half the tank out on the hwy. Running 80 on the hwy on cruise it just seem to have a intermittent pause to it. It will just have this little surge or miss to it, it is really tough to describe but if you have felt you will know what I am speaking of.

No check engine lights and sometimes you do not feel it but it is more often that you do. If you floor it it seems not to occur and really runs great, which is fun but not feasible.

Studder, shudder, skipping , miss, all these describe what I am feeling.

Please someone have had this problem or have some idea what may wrong