joe-96z1le

Had a problem this morning with my car. For ignition, I've got a DynaSpark,
MSD Dig 6 and MSD coil. While driving, car died at stop light but started right back up. Then noticed that car seemed to be missing and the tach was not reading right. The tach would keep dropping down to zero or close to it although the RPMs were higher. Headed back home and parked. Tried to re-start car and it wouldn't. Isolated MSD box and car still wouldn't start. Replaced ICM (Ignition module) with one I had layin' around and car started right up.

Now to my question. What exactly does the factory Ignition module do and would it cause the symptoms I experienced? Just wondering since I checked alot of wiring and may have fixed a loose wire too?

Thanks in advance for any replies.

84firebird

ignition module controls the coil, without it the coil doesnt fire, but yea it would cause the problems since your tach reads the number of times the coil fires. And ultimate death would be the module giving out, usually they just die and the only symptom is no spark, but eh, got ya home atleast. The engine would stop running when it didnt spin long enough inbetween the staggered sparks (if it missed on too many cylinders in a row)
A loose, or shorted ignition wire like the battery connection to the coil, could do the same thing. and i had that happen when an ignition wire found its way to the header.... not good

Daniel6718

factory icm connector gets hot and melts slightly and can cause your problem...mine did it tonite..gona buy a new connector tomaro