ecm1 fuse blows when ignition is turned on
 

2001 Chevy Blazer 4wd 4dr
Truck died while driving. ecm1 Fuse is blown. replaced fuse, as soon as ignition is turned on fuse blows instantly. disconnected everything on the circuit, replaced fuse, plugged in comonents 1 by 1 turning on ingnition and checking fuse. fuse held strong until I plugged in the connector for the fuel ingection system (7 pink wires and 2 black wires going into plug located between the throtle body and the distributer cap).
I dont know where to go from here. ingnition switch, injectors, or wire shorting between the fuse block and the injector plug, or shorting wire beyond the plug? Not sure if the truck suddenly dying while driving is a clue. not an intermittent problem.
sombody please help me.