I recently traced a no spark condition to the electronic spark controller that was hooked up to the HEI distributor in my 84 c-10 truck.Sometimes it had spark then all the sudden it didn't. After I ruled out all the other ignition components, I unhooked the connector that gives the ESC power from the hot (pink ) wire that goes into the distributor,and then plugged the pink wire directly into the dist.cap. I then unhooked the four wire connector that feeds into the module from the ESC controller .The green and black wires were cut and soldered together and the exposed wires were then covered with heat shrink tubing /electrical tape. The engine now starts up and runs great .The ESC was shorting out. This is a temporary fix.I have been running it like this for six months ,and haven't even adjusted the timing. My question about this is,when I finally get around to fixing it right , do I need to replace the whole distributor or can I just replace the module with one from an older HEI?What about the weights and springs/ vacuum advance canister? Should they be changed?The engine is just a 305 with a th350c trans.I also replaced quadrajet with an older non electrical feedback one . I have completely removed the ESC and all it's wiring.