I need some help /direction. I'm trying to track down a short to ground in the starting circuit of my 1994 Firebird. I was blowing the 10Amp fuse every time i switched key from off to even run before even engaging the starter. This immediately turns off the spark. The starter will engage and turn the car over and i hear the fuel pump turn on and prime. I smell fuel while turning engine over so I believe the injectors are pulsing.

Back to where I believe i need help. After blowing several 10amp fuses checking the starter wires and main wiring(large positive cables) for shorts i returned to the coil and icm as i wasnt getting the power there after the fuse blows. I unplugged the coil and icm together, not separate and no more blown fuse. So im thinking icm or coil or both are shorting to ground on the block and blowing the fuse. Car would start and run prior to parking to put a transmission in it. If there are videos or how to links i would appreciate the help. Parts are not too expensive but i wiuld like to diagnose the defective parts if they truly are the problem.
picture attatched are the parts bolted together i am trying to rule out.

 

You’re on the right track. Since the 10A fuse blows as soon as the key is turned to RUN and stops blowing when the coil and ICM are unplugged, the short is almost certainly in that ignition feed circuit. The starter, fuel pump, PCM, and injectors are doing what they should, so they’re not the cause. Next step is to unplug the coil and ICM separately and turn the key to RUN—if the fuse blows with only the coil connected, the coil is internally shorted; if it blows with only the ICM connected, the ICM (or its ground/mounting) is shorted. Also double-check the ICM mounting and ground to the block, since a bad ground there can cause an immediate fuse pop, especially after transmission work.

 

Havent been able to test unplugging the individual components due to weather and work schedule but should be able tomorrow. I had pulled the coil and icm assembly before the recent ice storm and was able to check the coil by checking values from the conection slots to coil wire post and all were equal in 8000 range(suspected aftermarket coil based on no gm number). Is there a way to bench test the icm with a volt meter before reinstalling? Before testing by plugging into car wiring and unhooking each component to test for short to ground?

 

After testing coil and eliminating the icm and coil by attemting to start with each unplugged individually I was able to start the car. Only ran it for a few seconds as i wasnt prepared to finishe what i needed the car to start for. The coil/icm bracket must not have been grounded properly and was causing it to blow the fuse. Thanks for the suggestion