It happened all of a sudden which makes me think leaking wells rather than the psi suddenly going higher, if it's not regulated now there is no regulator to fail to let the psi go higher, that & when it happened it also would not start so I dont think excessive psi would come from a fuel pump at cranking speed. . If the wells spring a minute leak it would flood it & make it hard to start & when it does start it'd be way rich as described.