99 caravan blows engine fuse

I put a 25 amp in place of the 20 amp fuse and it blows intermittently.
usually under power,more than half throttle.
I fill the gas tank thinking over heating fuel pump.seems to help.
but still can happen when cold.
van has 183k mi . new altinator,water pump, speed senser.
No check engine light.
I believe this fuse feeds;field wire 4 alt,O2 senser,fuel pump/injecters.
I fixed cold solders on instrument cluster connector.