Electronic ignition issue

The thing to determine is.................

is the cylinder(s) not firing because of ignition,

or or some other reason?

First, "rig" the plug wires one of two ways

Pull the boots up at the cap and loosen the plug wires, so that you can pull them out

OR stick small brads/ nails gently down beside each plug wire in the cap.

Get the engine warm and idling at it's "normal" idle, then take a grounded probe and ground each cap tower one at a time. Listen carefully and look at the tach. The engine should drop the same RPM or "sound the same" for each cylinder as you short it.

When you find a cylinder which makes no difference, get your ground probe down there and short the tower for that plug, as you pull the wire up out of the cap. Then slowly pull the ground probe back to get a "feel" for the spark.

DO NOT let the gap become more than about 3/8" or a little more, as an "open" spark wire can DAMAGE (I.E. "kill") the ECU

If the spark looks OK on the "bad" cylinders, make DARN sure the plug wires and plugs are OK on those cylinders. Either substitute known good plugs/ wires, or swap them to another cylinder and verify whether the problem follows the wire or plug

After you have done all the above, you should have a REAL good idea as to whether this is actually ignition or not.