https://hiluxsurf.co.uk/forum/hilux-surf-forums-technical/-3-0-turbo-diesel/86611-1kz-te-starting-problem
End of page 1, start of page 2. Just a quick Google guess.
^that's spill valve relay.
Maybe also check the condition of the capacitors in the ecu, make sure none have leaked out onto the board.
Ecu is under the dash behind the glove box box. According to that link relay is in there too for a surf, probably the same.