I got the similar problem with my 88 4Runner as Nick4runner's description. Mine starts up fine. The truck drives normally for about 5 min. and the EFI fuse blown of. I have noticed that whenever I give more gas (acceleracted), the fuse blows of sooner. The EFI is rated at 15 Amps. I usually installed a 30 Amps to limb home whenever that fuse blown.
I have checked for all the electrical shorts and found none. My fuel pump works fine. No clue to where to check next. Any info related to this problem is much appreciated.