What you need is
quantitative data meaning
numbers. Measure voltage at each coil RED terminal. Then wiggle wires everywhere while monitoring that voltage, should not ever change.
Getting useful data on grounding signal wire is more difficult, so borrow, rent, steal an oscilloscope if you can. Or at least get the solenoid test light. Either way will give us more useful data that we don't have now. Critical part is verifying you have clean square-waves coming out of ECU
and that they go all way down to
zero volts during spark interval. If not, there may be issues with wiring and/or ECU. Numbers we're looking for is something like this:
- +12v for 20ms
- 0v for 3ms
- +12v for 22ms
- 0v for 3ms
- etc...
Varying durations based upon RPM.