I'm sure it is trivial and cheap to fix but you have to find it. And the starter and relay switch, whatever that is, are not on the list of usual suspects. Unless you mean fuel pump relay. Oil pump? Do you mean you did a fuel pump? That is where mechanics like to start, just the opposite of where one should start for a good fix. You might need help finding or checking these but here is a list.


240 no-start:
check for timing belt breakage (not in this case, since intermittent)
fuel pump relay give it a whack to see if that corrects it
25 amp fuse (83-88)-not just blown, often a corroded contact
impulse sender (89-on)-easy to replace
wire at battery or fuel pump
fuel pump-replaced?
power stage-esoteric, usually a heat conductance issue with easy fix
89-on, suspect ECU loss of ground sydrome