i had something similar happen to me before on a different vehicle. it was a misfire on cylinder 4 then on 5. switch randomly. what it came down to was a cracked distributor cap. i know on the older dsm's that they dont have a distributor. just a coil pack. i would take it off and bring it to be tested. i dont know if you may have an issue with the computer either. but its just a thought to help you try and narrow results.

Thanks man. I tried a different ecu and nothing changed at the time either.

Same issue last year but I had faulty wire when my brother bought his eclipse so after some splicig and stuff shes fine. good luck figuring it out.