The fuel pumps feed the entire fuel distributor not any individual injector. IF, the pumps are supplying sufficient volume and pressure then any individual injector problem would be in the injector or distributor.

The perfect diagnosis would be a pressure test of the fuel pumps to rule out insufficient fuel to the distributor. If the other injectors/lines are working ok it is a quite safe assumption it's the distributor. Compare #1 to others.

In these circumstances I'd also do a compression test especially on #1.

Good luck!!!

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