smoking plug above fuel filter

[dirty661]

i just replaced my fuel pump and fuse for it. when i turn the key to aux mode i hear fuel pump pressurising but the plug end above the fuel filter/water seperator starts to smoke. when i pulled off its melted. any ideas on why this happens or the name of it?

[dirty661]

2002 moomba mobius lsv. has the indmar assault. i'll post some pics tommorror. what i have is there is 4 wires bundled before the fuel pump then 2 seperate to fuel pump (red+black) and the other 2 go to a plug that mounts to the fuel filter/water seperator. said plug completey melted and would smoke when i turned the key to aux. could this plug be the fuel pump relay?