Misfire 97 Merc Tracer 2.0 w/ Manual Trans

Okay, I have a stumble when accelerating (even gently). I get a trouble code of “misfire on cyl 4”. I’ve replaced the plugs twice, the coil pack twice, the MAF sensor, the wires twice, I’ve swapped the wires between 4 & 3, the injectors between 4 & 3. Problem does not follow wire, plug or injector. Compression is good. I understand that there are only two coils that fire a pair of cylinders. Not sure which cylinder is shared with #4 but all other cylinders are strong performers. I’m stumped. Help!!