Couple questions first. You have coil on plug ignition coils with integrated power transistors. That means the primary and secondary windings are in the coil. Do you have one specific coil that is failing or was this different ones that failed?
The most common things to cause this type of coil to fail is voltage spikes or faulty grounds as you stated. So we need to find out if the F16 ground at the front of the engine is intact. They all share the same ground so we need to find out if there were multiple coils failing.
Clearly this could be other things but I would start with this and go from there.
The ECM is most likely not causing the coils to fail as it only sends the low voltage signal to the coil where it interrupts the signal to cause the high voltage spike. It has happened but I would suspect the ground issue so let us know what you find with that and we can go from there. Thanks
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Tuesday, September 1st, 2020 AT 5:24 PM