Ignition module needs a ground

[Marty]

I learned something new today. I recently purchased two ignition modules from a bone yard and neither one worked. I returned one back and got another. Something didn't seem right though. I was thinking maybe the GN module is wired differently than the donor cars, and it is. But that is not what caused the modules not to fire. My third module did not fire either. After thinking about this problem some more, I decided to run a seperate ground wire to one of the three studs on the bottom of the module. What do you know, it fired. They all fired. When testing the modules, I just sat them on top of the bracket, not screwed down. I wrongly assumed that the grounding came into the module through the side harness. I am currently running a seperate grounding wire to the engine block from the module since the factory grounding goes through the module bracket that is attached to an aluminum manifold. The things you learn as you go.

 

[Steve Wood]

Yep, it must be well grounded....If it is loose, or poorly grounded, it will run like crap....

 

[The Radius Kid]

Yup.

 

[tazgn]

Boy, I feel better! I did that EXACT same thing a few years back when I didn't tighten down the front two nuts. The car missed BADLY when I gave it any throttle. Turns out after much $$$ in trying different things it was something as simple as that.

Derrick