I have been working for a week trying to figure out why I have a no spark issue. Hopefully someone here can help set me straight.

I have an 86 S10 Blazer 4WD with the 2.8 V6.


Initial problem:
Truck started misfiring/backfiring into the TBI under any amount of acceleration. This got worse over a 2 day period so I parked the truck and started hunting for the problem.

Found one of my injectors wasn't spitting right so after some cleaning and testing I ended up replacing it.


Secondary/current problem:
For some reason I decided it would be a good idea to take off the distributor cap and check cap, rotor, ignition control module, and coil. After everything tested fine I put it back together.

New problem arose from this, now I had no fuel coming my injectors at all.

So I replaced the ICM and the bad injector leaving me with proper fuel flow. However now I don't get any spark from the plugs or my ignition module. I tested by connecting a spark plug and grounding it out while cranking the engine.

So now I'm stuck with no spark and I have torn apart and reassembled everything related to the ignition coil and distributor with no success.

List of things replaced/checked:
New ignition coil - No spark with new or old coil
Ignition coil gets 12+ volts with key on and has good ground
New ICM
ICM gets 12+ volts and has a good ground
Pick up coil reads around 800ohms solid
Ground in distributor is good
Cap and rotor are new

So at this point I am lost and can only assume I have overlooked something or one of my new parts is malfunctioning.

I did notice a weird black wire not connected to anything on the three prong connector for the ICM. I am thinking this is the tach wire I have read about but maybe this has something to do with the no spark? I uploaded a photo of the connector is question.