Engine lost 4 cylinders over memorial day weekend and after a diagnosis of a bad IDM by the dealer I put a reman (reputable company - $400) IDM in and it started right up. Almost immediately I noticed an occasional hiccup and almost stall. Took a week of vacation and got home and took the truck out this weekend and had another minor couple hiccups. Started it up tonight and it became a steady miss, stumble and shut down every few minutes. When it first did this I replaced the CPS with a new one from the dealer. IPR is only a year old. No codes have been stored. Fuel pressure is where it should be. Monitored ICP pressure and IPR duty cycle and nothing strange going on there. I'm wondering if the reman IDM could be the problem?