Chevrolet Repair: ecm 1 fuse blows right away, chevrolet astro van, chassis wiring

Question
I Have a 1993 Chevrolet Astro van ext 4.3L v6. Every time you turn the key on it blows the ecm 1 fuse. It all started when it started popping thru the throttle body. Everyone said maybe fue pressure was low change the fuel filter first. Did so and popping decreased tremendously. Was testing when all of a sudden it was like someone turned the key off and I heard a pop at the fuse box. Looked and the ecm 1 fuse had blown. Changed fuse and it blew again when I turned on the key. Used a bobby pin to try and get it home(1/4 mile away). Turned on the key and pin became cherry red. Turned off key and pulled pin out immediately. Unhooked fuel puml wires,ecm module, and pickup module in distributor. Still blows fuse when key is turned on. Traced wire for ecm 1 and no ground out short. At wits end and ready to torch van. Any help greatly appreciated.   Thanx Jim

Answer
Hi Jim,
Go here,  http://www.autozone.com/az/cds/en_us/0900823d/80/11/91/01/0900823d80119101/repai...

and if that doesn't take you directly to the wire diagram, just go down to chassis wiring diagrams, and scroll down to the correct one, about figure ten, and look at the items connected to the ECM fuses.
See that one of them connects to the fuel pump relay, but doesn't make contact and run the pump until the relay is closed.

Some work with an ohm meter to find a dead short where there should be resistance is in order now.

Van