Backfire-after turning key off

KitCarlson said
There would have to be two faults, IGN1, and IGN2. But, it backfired, that happens if it has even cranked with fuel present, coil energized, then key off. If the ECM is not triggered, shorted, or coil- grounded, key off makes a spark. With V8, high probability it will pop on some cylinder, but not in correct time.
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Or if it has no ignition power in start but does when you let go of the key to run but it doesn't continue to run.
But this way it doesn't backfire, but just fires a cylinder but doesn't start.
Some call that a backfire, but I don't consider it one.