AMC Eagle Den Forum

The Mighty 258 => Engine Electrical Systems. => Topic started by: johnbendik on January 17, 2015, 08:34:55 PM

Title: 'Big Cap' ignition upgrade (the saga continues): grounding question
Post by: johnbendik on January 17, 2015, 08:34:55 PM
I am troubleshooting some new problems after doing an ignition upgrade (big cap and rotor, 8 mm wires, new plugs at .045 gap, Pertronix 3 ohm coil, resistor bypass, and new BWD CBE7P ignition module from Advance Auto).  The problems are some stutters and dropouts when accelerating.

I need a better understanding of the grounding problems that some posters have warned about.  They mention a grounding wire from the distributor harness to the fender that is sometimes not functional.  Where does this wire attach to the fender? 'Cause I can't find it.  (Which, of course, may be the problem)

I can see the flat ribbon strap grounding the engine to the frame, and there's a grounding point on the passenger side firewall where several auxiliary relays connect to.  But I don't see anything grounding to the fender except my newly installed headlight relays.

Thanks to all,
JB
Title: Re: 'Big Cap' ignition upgrade (the saga continues): grounding question
Post by: IowaEagle on January 17, 2015, 10:03:30 PM
Check the schematics in the AMC Eaglepedia to make sure.  But I think its grounded at the ICM.
Title: Re: 'Big Cap' ignition upgrade (the saga continues): grounding question
Post by: macdude443 on September 22, 2015, 02:42:09 PM
Just noticed this.  I know it's old.  Just to clarify, the black wire in the 3-wire ICM<->Distributor pickup harness is the ground.  The Dist/ICM grounds through the distributor base/block.  It is recommended by some to tap into that black wire and create a dedicated ground, as the dist base gets dirty and becomes an unreliable ground point.  If I remember right, the ICM enclosure is not grounded.