Have some electrical issues i thought someone could assist me with. Thought my fuel pump had died after I fixed my wiper linkage - turned out i wiggled one of the ecu cube shaped connections loose (red or white, maybe both). Can't check the fault codes with my obd2 BT scanner and phone, but the CEL is flashing and there's a clicking noise coming from the fuel pump relay.

Some more info:

Tightened both the loose electrical plugs behind teh ecu and put my fuel pump back in (made pressure as per the fuel pressure gauge leading to fuel rail and the vehicle started for a few seconds and then died). Starter is just turning the engine over and now no fuel pressure in the lines. I can hear the fuel pump when I turn the key to ACC, but there is a loud clicking coming from the fuel pump relay - when i pull the fuel pump fuse, the clicking stops.

Fuse is good, tried a known working fuel pump relay, and rewired the fuel pump. Pump makes noise but no pressure (if i swap positive and negative leads on the terminals there is no sound, so I know it is wired correctly FYI).

Thought maybe battery because low voltage but tried jumping off a diesel and it turned over very quickly but still couldn't get fuel pressure. Can hear the fuel pump working. Tried ignition switch - same problem. No other differences - dings the same way with the door open, all info is on cluster odo/trip, can't think of anything else i'm missing.

Any ideas? Wasn't able to find a solution using the search bar. Some tips in trouble shooting would help me greatly.