1990 oldsmobile regency
There is a relay, look under right side of the dash and find the fuse box there, the underside of the lid should have some sort of diagram of the fuse/relay layout. (if no diagram, check your owner's manual, if no owner's manual, just google for relay diagram for your make/model car). There should be several relays there, for things like the headlamps, defogger, interior lamps, etc.) find one with the same rating as the fuel pump relay and swap them, that will let you know if it was indeed the relay that was bad.
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