You are thinking too much..
Take a FP reading and see what you have ...if the reading drops off , you have a fuel problem..if it doesn't , you have a possible ignition problem .
If their is no ignition on HFM/SFI systems, the injectors shut down for cat protection.
Do a FP test............and check your wire harness...

FP specs for 104/HFM :

At idle
3.2-3.6 bar with vac line connected to FP regulator
3.7-4.2 w/o vac
2.5 bar after 30 min shut down of engine, key OFF.

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A Dalton