When it is HOT and idling do the wiggle test, I have seen a few that had problems with the CPS connector, not the CPS itself just the connector, as mine did, also make sure the gaps are correct PHASE 0.2-0.3mm, CPS 0.6-1.0mm, plugs 0.6mm, your coil could be on the way out as it does sound lecky in nature, but also could be amp, look at the wiring on the phase sensor see if it has disintergrated as they do!!.
Just a few ideas to keep,you busy
tabetha