No power to fuel pump
Your problem is most likey the corrosion at the connector under the car. Try temporarily bypassing the fuel pump circuit on the connector by running a jumper wire around the connector tap into the gray wire on both sides of the connector.
The ground for the fuel pump also goes through this connector, this is the black wire. It needs to have a good connection as well. If you are unable to clean up these connections and make them work, then the connector will need to be replaced. You will have to pull back the carpet and drill out the rivets to replace the connector.
What is that connector called? Do you have a part number?
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