95 Lexus ls400 Running rough loss of power

[95 ls400sucka]

So I was driving my 95 going bout 55 or 60 and all of a sudden it jerks Trac light comes on along with cel starts kinda puttering I'd call it. Then it was barely doing 40 rpms would barely go above 2 grand I still had like about another 10miles to make it home. so I thought I'd just try to push it home it's not like it died... it started acting really funny so I decided to stop looked under and seen my cats red hot wouldn't really stat and if it did it "putted" really hard decided to tow it home....it was throwing codes for o2s and maf I changed them different codes came up for a tps changed it still putting so I started looking on the forum everybody saying those kinda symptoms are o2s or maybe an ecu tps  an just a bunch of guess after beating my head on the wall for a few weeks I decided to go back check the fuses on the hood and efi2 I think is number 12 on the box was popped changed it.. fired right up like nothing ever happened so I put all the old parts back fired right up again it's bin fine every since... moral of the story check the fuses first....

[sha4000]

But why did the fuse blow in the first Place? Seems like it might happen again if you don't identify the underlying problem?