Just to explain myself; I think that it is an average battery that is causing your PGM to play up.
Possibly the capacitor (for one cylinder) in the Capacitor Discharge Ignition, is not getting enough of a charge (from the battery) between firing to be able to fire continuously.
When you remove the spark plug cap with the engine running, (which I do not recommend you do, by the way), the capacitor has time to recharge and will start to do its job properly again, for a little while anyway.
Possibly completely wrong, but just trying to help.
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[color=#808080][size=9]Yes,.. I too know how to waste Time and Money,...