What was the 155 temp. Internal CS or Rib temp?
Don't temp ribs (doesn't work).
3 or 4#? That one pd difference will make a difference in time.
Not sure why you went with 200. Sometimes people in an FEC do lower temps for more smoke.
My thoughts, until you get a "process" successful on your ribs go with a higher temp.
For that weight, those are spare ribs. Learn that term and see if they are full spares or trimmed down to St. Louis. If you don't know, check the Ribs 101 Video link at the top of this forum. Good info in there (from me).
I'd cook them at 250 for 3 hours then start checking. Lots of people like to foil, but I don't. Learn the toothpick test (here in the forum).
NOTE: EVERY time you open the door, you're dumping heat. So any times listed have to be extended to account for the time the door is open. Open, check, close as fast as you can.
For me? in my FEC I go with 275 for 4 hours for that weight range. 3# would be done between 3.5 and 4 hour and 4# would take about 30 to 60 more min.