97 s-10 p0301

Bought a 97 S-10 w/ 2.2 DIS and 5-spd. It wasn't long after I bought it that it started missing on #1. Along with a regular service, I changed all plugs, wires, & both coils. Ran fine for 3 days. Swapped coils, same. Put the old 2-3 coil back into the 1-4 coil position. Same. Went to salvage yard and bought a Ignition Control Module. Worked for a day. I've read on some forums where folks were talking about changing out the ECM. Are the referring to the Ignition Control Module (ICM)? The ICM is where the coil packs plug in to. I'm wondering if I've got a problem further downstream that is either not sending info to the ICM or is damaging the ICM. Not sure what track to take now. Chilton and Haynes manuals are useless.