I am having a problem with the ignition control module in my 87 HEI (Big Cap) Distributor. I have repeatedly changed the modules in order to get my noid light to blink. I have even swapped out the pickup coil once. The ICM is always installed with dielectric grease and the connections are tight.

My question, what can cause the ICM to blow? I think its getting some voltage spike or feedback but I don't know where. Can the coil cause it? bad grounds? spark plug gap? pickup coil? ECM mapping?