1993 Spark Problem

Engine misfiring. The check engine light isn't on. It doesnt do it all the time and doesnt do it at any given speed or RPM. Sometimes it does it on acceleration and sometimes when im just cruising along at the speed limit. My plugs and wires are good. I disconnected each plug wire at the coils and I checked each coil with an extra spark plug wire and a plug at the end of it and ran the car for a for a minute on each coil to see how they were firing. One of them fires randomly. No. 2. Sometimes it sparks and sometimes it doesnt. Could that be the coil itself? I read on one post in here where a computer went bad and wasn't telling the coil to fire. Could that be possible? Im gonna pick up a coilpack at the boneyard and replace the one that isn't firing correctly. Its cheap and i'll have some spares and figure it's worth a shot. I just wanted to put this thread in just in case that doesnt fix the problem and get some opinions.

Problem fixed. No more misfire. I picked up a coil pack at the boneyard for $40. Replaced all 3 of them since they were tested before they were sold.